DE102005017080B4 - Transmission method in a radio system with multiple transmission / reception branches in the base station - Google Patents

Abstract

Transmission method for use in a radio communication system, comprising a base station (1) having a plurality of n, but at least two independent transmission / reception branches, an air interface (3) and a multiplicity of subscriber stations (4), which radio communication system in the air interface with DS CDM / CDMA and an embedded TDM / TDMA and TDD and in which the slots formed by the TDM / TDMA in the code channels are initiated with preamble symbols,
characterized in that the base station in the downlink data type dependent uses different transmit diversity method for transmission to the subscriber stations, wherein
For preamble symbols which are spread with code sequences that do not have to match the code sequences for the data to be subsequently transmitted, OTD (Orthogonal Transmit Diversity), and
In a first method step, the preamble symbols are supplied via a splitter to a plurality of spreading devices whose number corresponds to the number n of the transmission branches;
In a second method step, the preamble symbols are spread with mutually orthogonal codes, and
• in a ...

Description

The The present invention relates to the field of devices and Method, the stationary Provide subscribers with wireless access to the Internet and the PSTN, specifically of the kind that both access to the internet as well as access to the PSTN are direct accesses, and one participant both accesses simultaneously and independent can use each other. In detail, the invention relates to the methods for the realization of the air interface, in particular the Transmit- and Receive diversity in the base station of such a radio system and the low-cost solution of the problem.

wireless Local access networks to the PSTN have always been in the last decade enforced more and are now commonly referred to as WLL (Wireless Local Loop). These access networks have been developed in such a way that they correspond to the Participants the basic telecommunication supply as POTS (Plain Old Telephone Service) or ISDN (Integrated Services Digital Network) and in the wake of the latest developments, access to the Internet offer high data rates. They differ in this respect from the mobile networks, the feature of mobility additionally to realize an already existing basic service, without being able to replace or replace them. A resulting distinguishing feature is that at WLL the subscriber stations no terminals represent, but interfaces for the connection of terminals after Dialing of the subscriber, while in mobile networks the Subscriber stations terminal function have.

was standing of the technique

One typical representatives of the first generation of WLL are those in [1] described devices and methods. For today's conditions are these facilities, including the developments carried out not sufficient. Access to the Internet has become indispensable Telecommunications offer. The existing WLL allow the Internet access via modem via the PSTN, but this is on Reason for the low bandwidths / data rates, the voice transmission provided in the air interface of WLL of the previous kind become ineffective. In addition, access to the PSTN is via WLL usually the only communication connection of the participant and the Assignment by an Internet access annoying and obstructing and the Acceptance of WLL detrimental.

meanwhile are diverse Further developments took place, especially the transition from analogue to digital transmission in the airinterface, increasing the data rates for modem and fax transmissions and the expansion of the service offer, including the broadband Access to the Internet, include. A typical representative of one such second generation of WLL are those described in [2] Facilities and procedures.

Currently In many places aspirations are underway, the limits of existing ones Overcome facilities with new solutions. Examples are described in the following.

The Application of several parallel transmission and reception branches in Radio systems, with the possibility the information about a variety of radio channels Transporting is increasingly becoming a promising process to increase the transmission capacity and / or to increase the transmission security proposed and put to practical use. The goal of this diversity is in it, the independence of Exploit fading processes in different radio channels for the improvement of the signal-to-noise ratio. With parallel transmitting and receiving units is in principle a Increase the transmission rate dependent on on the number of branches and the specific radio channel conditions possible.

The spatial diversity underlying these systems separate antennas and the possibility for the implementation of so-called MIMO systems (Multiple-Input-Multiple-Output) are current status of the technique. These are also proposed in particular for point-to-multipoint radio systems, which from a central base station and a plurality of external or Subscriber stations exist. These include, for example, all mobile radio systems like GSM, CDMA2000 and UMTS, as well as many WLAN systems and systems the fixed radio service such as wireless local loop or equivalent Data transmission systems (Wireless Internet Access).

Out cost considerations Many implementations focus on diversity through a plurality of parallel transmission and reception branches only in the base station to realize while the subscriber stations only over each have a send and receive branch. The following remarks relate exclusively on this case.

• – Antennendiversität, bei der die Nachricht wie beschrieben über unterschiedliche Antennen übertragen wird,
• – Polarisationsdiversität, bei der das Informationssignal über Antennenelemente mit unterschiedlicher Polarisation übertragen wird.

Diversity methods are used

• Antenna diversity, where the message is transmitted via different antennas as described,
• - Polarization diversity, in which the information signal is transmitted via antenna elements with different polarization.

These Procedures are additional used in combinations with time and / or frequency diversity. at time diversity the same message will be in sufficiently far apart Periods or at frequency diversity over different Transmit frequencies.

The described principles as well as the transmit direction (transmit diversity) as well as the receive direction (Receive Diversity).

• – Maximum-Ratio-Combining, bei dem alle n parallel empfangenen gleichartigen Signale mit dem jeweils geschätzten Fadingfaktor gewichtet und phasenrichtig addiert werden,
• – Equal-Gain-Combining, wobei alle n Empfangssignale ungewichtet und phasenrichtig addiert werden,
• – Selective-Combining, bei dem das jeweils leistungsstärkste der n Empfangsignale ausgewählt wird,
• – Switched-Combining, bei welchem ein über einem Mindestpegel liegendes Empfangssignal ausgewählt und im Weiteren dann auf einen anderen Empfangszweig umgeschaltet wird, wenn der Mindestpegel des Empfangssignals unterschritten wird.

With regard to the reception diversity, there are a multiplicity of methods which are suitable for evaluating or combining the signals emitted by a source and arriving in parallel in n reception branches. The goal of these strategies is signal reconstruction with higher accuracy over reception with a single receive branch. The most important combination strategies are:

• Maximum ratio combining, in which all n equal signals received in parallel are weighted with the respective estimated fading factor and added in the correct phase,
• Equal gain combining, where all n receive signals are added unweighted and in phase,
• - Selective-Combining, in which the most powerful of the n receive signals is selected,
• Switched combining, in which a received signal lying above a minimum level is selected and subsequently switched to another receiving branch when the minimum level of the received signal is undershot.

The Named methods differ considerably in this order in terms of their implementation effort, with maximum ratio combining most complex to implement. The achievable diversity gains Of course, the different methods depend on the concrete properties of the considered radio channels, but are fundamentally opposite to the implementation effort, so with maximum ratio combining in principle, the biggest gain in diversity can be achieved.

• – Space-Time Transmit Diversity (STTD) auf der Basis von • Blockcodes (Space-Time Block Codes), die systematisch Sendezweig und zu sendendes Symbol in festen Blöcken verknüpfen oder • Trelliscodes (Space-Time Trellis Codes), die diese Verknüpfung zwischen Sendeantenne und zu sendendem Symbol in rekursiver Weise realisieren.
• – Orthogonal Transmit Diversity (OTD) durch Spreizung der n Sendesignale mit unterschiedlichen, zueinander orthogonalen Codesequenzen
• – andere orthogonale Signalräume, z.B. Frequenz, Polarisation u.a.

Transmit diversity in multiple transmit antennas requires a signal coding, which is known to the receiver a priori, and allows the possible simple single-channel execution of the receiver. The best known principles are based on:

• Space-Time Transmit Diversity (STTD) based on: • Space-Time Block Codes (block-time block codes) that systematically link the transmission branch and the symbol to be transmitted in fixed blocks or • Trellis codes (Space-Time Trellis Codes) that link this between the transmitting antenna and to recieve a symbol to be sent in a recursive manner.
• Orthogonal Transmit Diversity (OTD) by spreading the n transmit signals with different, mutually orthogonal code sequences
• - other orthogonal signal spaces, eg frequency, polarization and others

at The encoding process, by combining with time diversity, will have a greater diversity gain achieved with OTD, since OTD uses only space diversity becomes. Furthermore it should be noted that for spreading codes of length k, a maximum of k different, mutually orthogonal sequences exist, so that in use theoretically available from OTD standing transmission capacity around the Factor N of the parallel transmission branches is reduced.

at The space-time method is the easiest way to implement block codes. Trelliscodes are more elaborate to implement with them but can be compared to block codes a higher one diversity gain be achieved. The with space-time method, based on block codes The achievable benefits are detailed in [3].

The best known and most basic block code based method is the principle described in [4] by Alamouti / Tarokh. Be here for a Transmit diversity with two transmission branches different reception concepts both at two reception branches (MIMO) and at only one reception branch described.

subsequent Publications mainly include the extension to larger numbers of sender branches and / or special designs the code matrices. Thus, in [5] a solution for 4 transmission branches and adapted code matrices presented. The solution described in [6] represents with respect to the above an evolution by different Phase or / and amplitude components in the transmission of the coded signals be brought in with.

A pure solution on the basis of trellis codes is described in [7]. majority but solutions become in which a trellis coder cascades with a block coder or combined, as shown for example in [8], [9] and [10] is the case. In [11] a solution is described in which a turbo product coder is cascaded with a trellis encoder. In [12] will be additional to a solution the basis of a trellis coder nor frequency diversity applied.

OTD is only in rare cases used in pure form, as for example in [13].

In [14] becomes a solution described, which optionally allows the use of OTD or STTD. In the same way, this applies to [15], but here is the additional Switchability of the device between the two methods claimed.

In a variety of cases However, a combination with other methods. So include the solutions described in [16] and [17] are also optional Use of OTD or STTD, in both cases combined with a phase sweep transmit diversity. In [18] OTD is cascaded applied with a Trelliscoder.

In [19] describes a device that universally handles all procedures the broadcast diversity allowed. Basic principle is that for the modulation processed data is passed to a "TX diversity processor", which by a device "Transmission Mode Control " the respective diversity method is set. The diversity channels will be independently prepared by the diversity method using OFDM for the broadcast. As possible Diversity techniques are Frequency Transmit Diversity, Walsh Transmit Diversity, STTD, Walsh STTD, Frequency STTD, Frequency Walsh diversity and Frequency Walsh STTD named.

specific solutions for the Application in CDMA systems are described in [20] and [21].

In [22] becomes a modified method and device for a mobile radio system described in which only the pilot channels with such an orthogonal Transmit diversity be while the rest traffic channels after conventional Way to be sent.

All presented diversity or MIMO principles can in principle independently from a concrete signal structure such as modulation methods, access methods, Duplex schemes and the like be applied. However, you have to the specific boundary conditions and requirements of the signal structures be taken into account at low cost Method and transmission or receiver structures to determine as well as to the conditions of the specific radio channel adapted performance to reach.

In The following considerations concentrate on this context to a CDMA-based radio system. CDMA systems with direct sequence band spreading are used in many mobile and WLL systems (e.g., UMTS, CDMA2000). CDMA systems become common used where, with considerable influences through multipath propagation and as a result of this frequency-selective radio channels is to be expected. The CDMA systems are characterized by a high resistance to such disturbances Multipath propagation, since any signal echoes to the so-called Process gain, the ratio the transmission rate of the spread signal (chip rate) at the rate of the unspread signal (Symbol or bitrate), suppressed become.

However, in the predominantly used asynchronous CDMA methods, there are considerable multiuser interferences due to crosstalk between not perfectly orthogonal spreading codes. For this purpose, the following simplified formula for the achievable signal-to-noise ratio Eb / No can be specified:

S_av

– Empfangsleistung pro Codesequenz (Nutzer),

R_b

– Symbol- bzw. Bitrate

W

– Übertragungsrate des gespreizten Signals (Chiprate)

M

– Anzahl der parallelen Codesequenzen (Nutzer)

η

– Rauschleistung des Empfängers

Where:

S _av

- receive power per code sequence (user),

R _b

- Symbol or bitrate

W

- transmission rate of the spread signal (chip rate)

M

- Number of parallel code sequences (users)

η

- Noise power of the receiver

Using formula (1), the maximum number of users that can simultaneously operate in a frequency band simultaneously can be estimated:

Here, the bottom bracket means the largest integer, which is not greater than the parenthesized value and W / R _b, the spreading factor or Spreizgewinn.

So can at a required Eb / No of 8 dB and a spread gain of 64 maximum M = 11 transmitted parallel data transmissions in a certain frequency band become. With M = 22 parallel data transmissions, the signal-to-noise ratio would be Reduce Eb / No to 5 dB. Improvements are made by using so-called Multi-user detectors or interference-Canceller achieved in which However, these are complex procedures that are very powerful and require expensive signal processing base.

A different possibility consists in the use of spreading sequences from a family orthogonal to each other Codes. This special approach of a DS-CDMA (Direct Sequence CDMA) requires an exact time synchronization of all transmissions, since the orthogonality condition only for a certain code phase applies, which must be exactly adhered to. In one Therefore, point-to-multipoint system must especially in the transfer direction from the outstations to the base station a high synchronization effort are operated, because here each other independent Sending sources. However, it can be synonymous with ideal synchronization in practice basically no full code orthogonality is saved in the receiver, because orthogonality losses also as a result of further effects such as multipath propagation, band limitation and the like. occur. Nevertheless, a larger number of traffic channels compared to that determined by formula (2) for asynchronous CDMA maximum number are allowed.

at the combination of a CDMA method with spatial transmit diversity over several Antennas potentiate these multiuser interference effects, so that an application seems less promising and so far little research has been done yet. Descriptions in this regard Procedures and arrangements by the appropriate number of parallel Transmitting and receiving trains are extremely expensive, can be found for example in US2004105489. There is an application of DS-CDMA transmission method in one MIMO system described. The prior art is also referred to [23]. directed.

task

• – geringe Multiuserinterferenzen,
• – hohe Übertragungskapazität,
• – geringer Implementierungsaufwand.

The object of the method according to the invention is then to use spatial diversity methods in a stationary radio system with point-to-multipoint structure and DS-CDMA access method. These should be implemented as transmit and receive diversity in the area of the base station and have the following additional features:

• Low multiuser interference,
• - high transmission capacity,
• - low implementation effort.

The preferably high transmission capacity given Radio channel bandwidth should primarily only by the number of to disposal standing orthogonal spreading codes are limited and the transmission security should be opposite an equivalent Method without spatial diversity elevated be. The solution of Task is carried out according to the inventive method accordingly the features of the claims 1 and 9. An essential aspect is that different and graduated spatial diversity principles be used. Depending on the type, source and sink of the intended information transfer becomes diversity as orthogonal transmit diversity, space-time coding or switched selective broadcast over executed a transmission branch.

The means that preambles, Broadcast channels (BCH - Bradcast Channel) and traffic channels (TCH traffic Channel) the broadcasting diversity be implemented differently.

The preambles are transmitted by the base station via OTD over all transmission branches. The spreading sequences must not with the code sequences for BCH and TCH match. The transmission takes place in all transmission branches with identical reference carrier phase Zero and equal transmission power, the symbol energy being greater than those chosen by BCH and TCH is less than the sum of the symbol energies of all TCHs.

The preambles serve the subscriber station in addition to the synchronization of all receiver components the determination of the optimal reception reference for the outstations and the estimation of the impulse response of the Radio channels. Because the linkage of transmission branch and code sequence a-priori all outstations is known, the outstations the individual radio channel estimates uniquely assign each transmit branch of the base station. The occurring Multiuser interferences are significantly limited because only preambles correspond the number of parallel transmission trains usually not more than four in practice.

• – Die ermittelten Werte werden an den Space-Time Decoder übergeben, welcher die BCH-Signale dekodiert.
• – Die ermittelten Werte dienen dazu, den für die Übertragung der TCH-Signale optimalen Sendezweig der Basisstation kontinuierlich aktuell zu bestimmen. Nachfolgend wird im Uplink an die Basisstation eine Information über den für die TCH-Übertragung zu verwendenden Sendezweig übertragen.

The estimation of the impulse response of the radio channels is used as follows:

• The determined values are transferred to the space-time decoder, which decodes the BCH signals.
• The values determined serve to continuously determine the transmission branch of the base station which is optimal for the transmission of the TCH signals. Subsequently, information about the transmission branch to be used for the TCH transmission is transmitted in the uplink to the base station.

The BCH signals are encoded in the base station Space-Time and the Output signals of the space-time Coder in parallel with a same code sequence from the set of for the TCH available standing code sequences spread and transmitted in parallel over all transmission branches. It can more than one BCH can be used. The spreading codes for the / BCH will be in the downlink period without BCH transmission for TCH used.

In the subscriber station become the space-time coded BCH signals after despreading fed to a space-time decoder. The space-time decoder uses those from the preamble reception resulting estimate the impulse response of the radio channels for the Decoding. For Space-time decoding is an essential input. Other known systems, such as in [4], guide the estimation of the impulse response the radio channels from the space-time coded received signal. different Arrangements and configurations of a channel estimator are named in the and also other writings. The corresponding present Invention from the preamble reception however, have a higher accuracy than a channel estimate a space-time coded signal, so that the decoding of the BCH signals more secure becomes. At the same time, an effort reduction occurs because of the channel estimation Hand of the preambles easier to implement than the channel estimation based on a space-time coded signal.

The TCHs are transmitted by the base station only in one transmission branch at a time. The transmission branch to be used is as described above determined by the subscriber station. If there is a message from the subscriber station not or not yet, so chooses the base station, from the Acceptance of reciprocity starting, the transmitting branch of that RF module, the best Reception of preamble broadcasts the subscriber station delivers. The procedure ensures a clear diversity gain and avoids the increase the multiuser interference, as described above would occur when transmitting the TCH in all transmission branches. It can even statistically average a reduction in multiuser interference be assumed if an equal distribution of active subscriber stations and so that TCH takes place on the transmission branches of the base station and the subscriber station those not selected by her Transmission branches with significantly reduced input power receives.

One Another advantage of the method according to the invention is the reduction the power backoff and thus the performance class, size, price and power turnover of the amplifiers the base station, since typically the number of parallel to send code channels per transmit branch is less than their total number.

In the base station are also stepped in the receive direction diversity method implemented.

• – zur Dekodierung des Inhalts als Diversitätsverfahren Maximum-Ratio-Combining angewandt, welches den höchsten Diversitätsgewinn bietet, das heißt, die Symbolentscheidung wird an Hand der phasenkorrigierten Addition aller Empfangswerte durchgeführt (Maximum-Likelihood-Prinzip). Der im Verhältnis zu anderen oben genannten Verfahren höchste Aufwand relativiert sich, da die Anwendung sich auf einen Codekanal eines Zeitschlitzes der Uplinkperiode beschränkt.
• – der für die Übertragung von der jeweiligen Teilnehmerstation optimale Empfangszweig bestimmt, wofür als Kriterium die einfache Detektion und Vergleich der Leistung in den Empfangszweigen dient.

The receipt of the random access channel (RACH) takes place in all reception branches and it becomes

• - Maximum factor ratio combining applied for decoding the content as a diversity method, which means that the symbol decision is performed on the basis of the phase-corrected addition of all received values (maximum likelihood principle). The highest effort in relation to other methods mentioned above is relative, since the application is limited to a code channel of a time slot of the uplink period.
• - Determines the optimum for the transmission of the respective subscriber station reception branch, for which the simple detection and comparison of the power in the reception branches serves as a criterion.

Of the Reception of the preamble broadcast a subscriber station takes place in all reception branches and it becomes the for the transfer determined by the respective subscriber station optimal reception branch, for what Criterion the simple detection and comparison of the performance in the Reception branches serves. This is possible with the same precision as in the RACH since preambles exclusiv always only from a subscriber station with about the same Channel power as in TCH are sent. For this purpose, k timeslots will be used per uplink period and m code channels a superframe formed with k * m timeslots. Within this superframe will be in every timeslot each one of the code channels and thus a subscriber station exclusively assigned the authorization, the Data transmission a preamble broadcast preceded. The assignment rule is as a priori determination in the Communication system known. The reception of the RACH and the preamble broadcasts will continue to be used in the base station to time differences to recognize the broadcasts of the subscriber station and control commands to correct the subscriber station, the RACH only in the Phase of the connection establishment is effective and the preamble shipments while the existence of the connection is a continuous update cause.

Of the Reception of the TCH takes place respectively in the reception branch, the corresponding the above statements Reception of RACH or preamble broadcasts as optimal for the transfer was determined by the respective subscriber station, where also applies that the RACH is only effective in the connection establishment phase and the Präambelsendungen while the existence of the connection is a continuous update cause.

It can statistically mean a reduction in multiuser interference be assumed if an equal distribution of active subscriber stations and thus TCH takes place on the reception branches of the base station and the reception power of the TCH in each of them not selected reception branches is significantly reduced. The method also causes that everybody TCH is despread and decoded only in one of the reception branches, so that the for the Sum of all TCH required total effort is not significantly greater as with only one reception branch without diversity.

embodiment

One embodiment The invention will be explained in more detail with reference to the accompanying drawings. Show it:

1 the architecture of the radio communication system in its entirety,

2 the establishment of the base station for the transmission of the preamble symbols by means of OTD (Orthogonal Transmit Diversity),

3 the establishment of the base station for the transmission of the BCH (broadcast channel) by means of STTD (Space Time Transmit Diversity),

4 a device of the base station for the transmission of a TCH (Traffic Channel) in the transmission branches selected for the transmission,

5 a transmission branch of the RF modules of the base station,

6 the structure of the downlink period in the TDD (Time Division Duplex),

7 the structure of the uplink period in TDD (Time Division Duplex),

8th the receiving complex of the subscriber station,

9 a reception branch of the RF modules of the base station

10 the setup of the base station for receiving the RACH

11 the establishment of the base station for preamble reception

12 means of the base station for receiving a TCH

Either the previous general descriptions as well as the following detailed description have only exemplary character as possible embodiments the method according to the invention and restrict the requirements not to the invention.

1 describes the architecture of a device for implementing the method according to the invention. A base station 1 has n, but at least 2, transmit / receive modules 2 as interfaces to the air interface 3 for the wireless connection to a plurality of subscriber stations 4 , The base station 1 also has an interface to the PSTN 5 and an interface to the Internet 6 , over which both POTS and ISDN as well as higher-rate Internet connections are served.

The subscriber stations 4 have a send / receive module as interface to the air interface 3 for the wireless connection to the base station 1 , Furthermore, the subscriber stations have 4 one PSTN subscriber interface each 7 , which is designed for POTS (TIP / RING, a / b) or ISDN (basic connection, 2B + D), and an Ethernet interface 8th , which is intended for Internet access via PC.

The shown radio communication system works in the air interface with DS CDM / CDMA and an embedded TDM / TDMA and TDD.

Based on 2 The preparation and transmission of the preamble symbols in the downlink, which uses OTD (Orthogonal Transmit Diversity), are described. The slots formed by the TDM / TDMA are introduced with preamble symbols, for the spreading of which orthogonal codes are used which do not have to match the codes of the subsequent TCH (Traffic Channels).

The preamble symbols become a splitter 12 over its entrance 13 fed. The splitter distributes the preamble symbols in parallel to n spreading devices 14 in which the spreading takes place with n orthogonal codes passing through inputs 15 be supplied. The thus splayed n signals are each via one of the transmission branches 10 ( 5 ) of the transmitting / receiving modules 2 the base station radiated. As a priori determination is that the transmission of the spread preamble symbols with the reference carrier phase zero and with exactly the same transmission power in the transmitting branches, wherein the symbol energy is greater than that in the individual code channel, but smaller than the sum of all code channels.

Based on 3 The processing and transmission of the data of the BCH (Broadcast Channel) in the downlink, which uses STTD (Space Time Transmit Diversity), are described. The data of the BCH are transmitted in one of the slots formed by the TDM / TDMA, preferably in the first slot of the downlink period. The n different space-time coded data sequences are transmitted in all transmission branches in the same code channel. Since the BCH occupies the code channel only in this one slot, the remaining slots are used as TCH.

The BCH data becomes an assembly for FEC coding and interleaving 20 over the entrance 21 fed. The coded signals are from a demultiplexer 22 distributed on n signal paths as signals S1 to Sn and to an STC (Space Time Coder) 23 to hand over. The STC provides at its outputs the space-time coded signals T1 to Tn, which are in n spreading devices 24 be spread. The spreading takes place with a code sequence that is the same for all of the stock of TCH code sequences that are received via an input 25 is supplied. The signals thus spread are then via each one of the transmission branches 10 ( 5 ) of the transmitting / receiving modules 2 the base station radiated.

• – sofern beim Verbindungsaufbau oder aus anderen Gründen noch keine Anforderung von der Teilnehmerstation vorliegt, durch die Basisstation durch Auswertung des Receive Diversity unter Annahme der Reziprozität von Up- und Downlinkübertragung, indem für die Sendung der Sendezweig 10 (5) der Sende-/Empfangsbaugruppe 2 gewählt wird, die den besten Empfang der Signale der Teilnehmerstation liefert. Die Ermittlung der entsprechenden Sende-/Empfangseinrichtung erfolgt an Hand der Sendung der Teilnehmerstation im RACH oder der Präambelsendungen, indem diese in allen Empfangszweigen parallel dekodiert werden und an Hand der detektierten Leistung die Auswahl nach dem Prinzip des Selective-Combining getroffen wird, oder,
• – nach Vorliegen einer Rückinformation der Teilnehmerstation über den zu wählenden Sendezweig entsprechend dieser Anforderung, welche Vorrang vor dem Ergebnis des Receive Diversity der Basisstation besitzt. Die Teilnehmerstation ermittelt den von der Basisstation zu wählenden Sendezweig nach Anspruch 3 aus dem Empfang der Präambeln, indem die Leistung der Präambelsymbole detektiert und als Kriterium für die Auswahl nach dem Prinzip des Selective-Combining benutzt wird.

Based on 4 The processing and transmission of the data of the TCH (Traffic Channel) are described in the downlink. The TCH data are in each case emitted only in the transmission branch, which was determined to be optimal for reception in the subscriber station. The determination of the transmission branch is carried out according to claims 7 and 9,

• - If the connection station or for other reasons no request from the subscriber station is present, by the base station by evaluating the Receive Diversity assuming the Rezip roup of uplink and downlink transmission by sending the transmission branch 10 ( 5 ) of the transmitting / receiving module 2 is chosen, which provides the best reception of the signals of the subscriber station. The determination of the corresponding transceiver takes place on the basis of the transmission of the subscriber station in the RACH or the preamble broadcasts, by decoding them in parallel in all reception branches and selecting on the basis of the detected power selection according to the principle of selective combining, or
• - If there is a return information of the subscriber station on the transmission branch to be selected according to this requirement, which takes precedence over the result of the receive diversity of the base station. The subscriber station determines the transmission path to be selected by the base station according to claim 3 from the reception of the preambles by detecting the power of the preamble symbols and using it as a criterion for selection according to the principle of selective combining.

The TCH data becomes an assembly for FEC coding and interleaving 30 over the entrance 31 fed. The coded TCH signals are in a spreading device 32 spread. The spreading takes place with one of the TCH code sequences passing through the input 33 is supplied. The spread signal is switched by a selector switch 34 which is from the central control via an input 35 is placed on one of the transmission branches 10 ( 5 ) for transmission.

• – einem Eingang für Präambeldaten 41,
• – einem Eingang für BCH-Daten 42,
• – den Eingängen 1 bis m für TCH-Daten 43 und
• – einem Steuereingang 44.

In 5 is the sending branch 10 one of the n RF modules 2 the base station shown. The transmission branch 10 includes an adder 40 With

• - an input for preamble data 41 .
• An input for BCH data 42 .
• - the entrances 1 to m for TCH data 43 and
• - a control input 44 ,

The data are from the modules according to the 2 . 3 and 4 provided, wherein the central control of the base station, the provision according to the time structure of the downlink period after 6 performs. The added signals pass through a digital-to-analog converter for transmission 45 , a modulator 46 and amplifiers 47 , Not shown is that between amplifiers 47 and antenna, an antenna switch is arranged, which realizes the alternative use of the antenna for transmitting and receiving operation.

The adder 40 includes means for selectively providing power to the inputs for TCH data 43 applied signals. The control is carried out by the central control via a control input 44 based on feedback from the subscriber station of claim 6, wherein the subscriber station, upon receiving each of the TCHs assigned to it, carries out an assessment of the reception quality, using as criterion of signal-to-interference ratio (SIR) each of the TCHs; and sends, based on the determined SIR values, a return information for controlling the transmission power of the respective TCH to the base station.

In 6 is the structure of the downlink period 50 representing a variable number of j timeslots 51 each comprising a preamble broadcast 52 and a data block with m code channels (TCH) 57 consist. In the vertical, the relative symbol energy is shown in the parallel channels. The transmission of the preambles is carried out by means of OTD in all transmission branches, wherein the symbol energy corresponding to representation is greater than in the TCH. The preambles are spread with code sequences that are not identical to the code sequences of the TCH. In the first timeslot, at least one of the code channels is BCH 53 used. The transmission of the BCH is space-time coded in all transmission branches. In the following timeslots, this code channel is called TCH 55 used. The TCHs are only sent in one of the transmission branches as described above. In 7 the structure of the uplink period is shown, each comprising the RACH 60 , the uplink frame 61 with a variable number of k timeslots 62 , each comprising a preamble 67 and a data block with m code channels (TCH) 69 ,

• – die Verbindungsanforderung einer Teilnehmerstation zu erkennen, wofür als Receive-Diversity-Verfahren Maximum-Ratio-Combining zur Anwendung kommt,
• – zeitliche Abweichungen der Sendungen der Teilnehmerstation entsprechend Anspruch 12 zu erkennen, wofür als Receive-Diversity-Verfahren Selective-Combining zur Anwendung kommt, und über Steuerbefehle an die Teilnehmerstation zu korrigieren, und
• – den für den Empfang der TCH-Sendungen der Teilnehmerstation optimalen Empfangszweig 110 (12) zu bestimmen, wofür als Receive-Diversity-Verfahren Selective-Combining zur Anwendung kommt.

The RACH as Random Access Channel is used in the base station according to claim 9, provided there is no hazard of two subscriber stations

• Recognize the connection request of a subscriber station, for which maximum ratio combining is used as the receive diversity method,
• - To detect temporal deviations of the broadcasts of the subscriber station according to claim 12, for which as receive-diversity method Selective-Combining is used, and to correct over control commands to the subscriber station, and
• - The optimum for receiving the TCH transmissions of the subscriber station receiving branch 110 ( 12 ) to determine what is used as receive diversity method Selective Combining.

The preambles are exclusively ever sent by a subscriber station with approximately the same or slightly greater channel power than the data in the TCH. For this, k timeslots per uplink period 59 and m code channels 66 a superframe formed with k * m timeslots. Within this superframe, in each timeslot, in each case one of the code channels is exclusively assigned the authorization to precede the data transmission with a preamble transmission. The assignment rule is known as a priori determination in the communication system. For example, in the case of the current uplink frame in the first timeslot, the preamble is exemplary 63 the TCH 64 , in the second timeslot the preamble 65 the TCH 66 and in the k-th timeslot the preamble 67 the kth TCH 68 assigned. In the following uplink period, the method is updated until all TCHs have been assigned a preamble broadcast once.

• – zeitliche Abweichungen der Sendungen der Teilnehmerstation entsprechend Anspruch 12 zu erkennen, wofür als Receive-Diversity-Verfahren Selective-Combining zur Anwendung kommt, und über Steuerbefehle an die Teilnehmerstation zu korrigieren, und
• – den für den Empfang der TCH-Sendungen der Teilnehmerstation optimalen Empfangszweig 110 (12) zu bestimmen, wofür als Receive-Diversity-Verfahren Selective-Combining zur Anwendung kommt.

The preamble broadcasts are used in the base station according to claim 9 to

• - To detect temporal deviations of the broadcasts of the subscriber station according to claim 12, for which as receive-diversity method Selective-Combining is used, and to correct over control commands to the subscriber station, and
• - The optimum for receiving the TCH transmissions of the subscriber station receiving branch 110 ( 12 ) to determine what is used as receive-diversity method Selective-Combining.

• – bei niedrigratigen und fehlertoleranten Sprachverbindungen, welche in der Uplinkperiode nur in einem Timeslot einen Codekanal belegen, einmal innerhalb des Überrahmens von k*m Timeslots eine Präambelsendung vorgenommen wird, während
• – bei höherratigen und fehlerkritischen Datenverbindungen, die in allen Timeslots einen oder auch mehrere Codekanäle belegen, entsprechend häufiger Präambelsendungen vorgenommen werden, und somit bei kritischen Verbindungen in kürzeren Abständen Korrekturen der Zeitablage und Sendeleistung vorgenommen werden.

The method of exclusive preamble broadcasts causes

• During low-rate and fault-tolerant speech connections, which in the uplink period only occupy a code channel in a timeslot, a preamble broadcast is performed once within the superframe of k * m timeslots, while
• - in the case of higher-rate and error-critical data connections which occupy one or more code channels in all timeslots, correspondingly frequent preamble transmissions are carried out, and thus corrections of the time deposit and transmission power are made at shorter intervals for critical connections.

In 8th the reception complex of the subscriber station is shown. This includes the analogue reception branch 74 the RF module of the subscriber station, an analog-to-digital converter 75 and a splinter 76 via which the received signals are provided to the modules for the detection of the different types of data.

• – an n Ausgängen 80 die geschätzten komplexen Kanalimpulsantworten an den Space-Time Decoder 87 übergibt und
• – ein Receive Diversity nach dem Prinzip des Selective-Combining realisiert und an einem Ausgang 81 die Information über den Kanal mit der höchsten Empfangsleistung ausgibt, welche Information von der Teilnehmerstation als Rückmeldung an die Basisstation gesendet wird zwecks Bestimmung des Kanals, in welchem die Übertragung der TCH-Daten erfolgen soll.

The preambles are detected in n despreading devices 77 , each inputs 78 for the spreading codes of the preambles. The output signals of these n parallel branches are sent to a device for channel estimation 79 for n channels passed, which

• - at n outputs 80 the estimated complex channel impulse responses to the space-time decoder 87 passes and
• - realized a receive diversity according to the principle of selective combining and at an output 81 the information on the channel with the highest received power outputs, which information is sent from the subscriber station as a response to the base station for the purpose of determining the channel in which the transmission of the TCH data is to take place.

The detection of the BCH data includes the despreading device 85 with the entrance 86 for the spreading code of the BCH data, the space-time decoder 87 , the multiplexer 88 and the assembly 89 with deinterleaver and fec decoder, which at their output 90 provides the BCH data. The space-time decoder 87 uses the device for channel estimation during decoding 79 passed complex channel impulse responses resulting from the evaluation of the preamble reception.

• – übergibt die Daten an die Baugruppe 98 mit Deinterleaver und FEC-Decoder, welche an ihrem Ausgang 99 die TCH-Daten bereitstellt und
• – gibt an einem Ausgang 97 den SIR-Wert aus, auf Grund welchen Wertes die Teilnehmerstation bei Bedarf eine Rückmeldung an die Basisstation sendet zwecks Veränderung der Sendeleistung des Codekanals in der Basisstation.

A subscriber station can have several modules for TCH reception 93 for the parallel detection of multiple code channels, each having a despreading device 94 with an entrance 95 for the spreading code of the TCH data. The allocation of the spreading code is carried out by the base station during connection establishment and may also be changed during the connection state. A downstream symbol decision maker and SIR evaluator 96

• - transfers the data to the module 98 with deinterleaver and fec decoder, which at their output 99 providing the TCH data and
• - indicates at an exit 97 the SIR value on the basis of which value the subscriber station, if necessary sends a feedback to the base station for the purpose of changing the transmission power of the code channel in the base station.

• – einen Ausgang 115 zur Anschaltung der Einrichtung der Basisstation für Detektion des RACH,
• – einen Ausgang 116 zur Anschaltung der Einrichtung der Basisstation für Detektion der Präambeldaten und
• – Ausgänge 1 bis m 117 zur Anschaltung der Einrichtungen der Basisstation für Detektion der TCH- Daten.

In 9 is the reception branch 110 one of the n RF modules 2 the base station shown. The reception branch 110 includes an input amplifier 111 followed by demodulator 112 , Analog-to-digital converter 113 and splinters 114 , The splinter 114 has

• - an exit 115 for connecting the device of the base station for detection of the RACH,
• - an exit 116 for connecting the device of the base station for detection of the preamble data and
• - outputs 1 to m 117 for connecting the devices of the base station for detecting the TCH data.

• – an eine Einrichtung 118 zur Dekodierung mittels Maximum Ratio Combining (Maximum Likelihood Verfahren) und
• – an eine Einrichtung 135 zur Bestimmung des Delaywertes, der die Ablage des Empfangszeitpunktes der Sendung der Teilnehmerstation vom Optimalwert beinhaltet,

übergeben. Die Einrichtung 118 gibt an einem Ausgang 129 die RACH-Daten und an einem weiteren Ausgang 130 die Information über den für die Übertragung von der jeweiligen Teilnehmerstation optimalen Empfangszweig aus, wofür als Kriterium die detektierte Leistung in den Empfangszweigen genutzt wird. Letztere Information wird

• – der zentralen Steuerung bereitgestellt, welche auf Grund dieser Information realisiert, daß die Detektion der TCH-Daten der betreffenden Teilnehmerstation in dem ausgewählten Empfangszweig erfolgt, und des weiteren
• – der Speichereinrichtung 136 zur Auswahl des Delaywertes bereitgestellt, welcher in dem als optimal ermittelten Empfangszweig gemessen wurde.

In 10 the setup of the base station for receiving the RACH is shown. The demodulated and AD-converted received signals are received by the receiving branches 110 the RF modules 2 provided to the base station. The signals are in the n despreading devices 112 which the code sequence of the RACH via the input 113 is fed in parallel, despread and then

• - to a facility 118 for decoding by means of Maximum Ratio Combining (Maximum Likelihood Method) and
• - to a facility 135 for determining the delay value, which includes the storage of the reception time of the transmission of the subscriber station from the optimum value,

to hand over. The device 118 gives at an exit 129 the RACH data and at another output 130 the information about the optimal for the transmission of the respective subscriber station reception branch, for which the detected power is used in the reception branches as a criterion. The latter information becomes

• - Provided to the central controller, which realizes on the basis of this information that the detection of the TCH data of the relevant subscriber station in the selected reception branch takes place, and further
• - the storage device 136 for the selection of the delay value, which was measured in the optimally determined reception branch.

The device 135 transfers the measured values to the storage device 136 , From these measured values, as described above, the value which was determined in the reception branch with the best reception and at the output is selected 137 provided. Said delay value is sent by the base station as feedback information for controlling the start time of the transmissions of the subscriber station to the respective subscriber station.

• – an eine Einrichtung 148 übergeben, welche den für die Übertragung von der jeweiligen Teilnehmerstation optimalen Empfangszweig bestimmt, wofür als Kriterium die detektierte Leistung in den Empfangszweigen genutzt wird. und diese Information an einem Ausgang 150 ausgibt, sowie
• – an eine Einrichtung 155 zur Bestimmung des Delaywertes übergeben, der die Ablage des Empfangszeitpunktes der Sendung der Teilnehmerstation vom Optimalwert beinhaltet.

In 11 the setup of the base station for preamble reception is shown. The demodulated and AD-converted received signals are received by the receiving branches 110 the RF modules 2 provided to the base station. The signals are in the n despreading devices 142 which the preamble code sequence passes through the input 143 is fed in parallel, despread and then

• - to a facility 148 passed, which determines the optimum for the transmission of the respective subscriber station reception branch, for which the detected power is used in the reception branches as a criterion. and this information at an exit 150 spends as well
• - to a facility 155 for the determination of the delay value, which includes the storage of the reception time of the transmission of the subscriber station from the optimum value.

• – der zentralen Steuerung bereitgestellt, welche auf Grund dieser Information realisiert, daß die Detektion der TCH-Daten der betreffenden Teilnehmerstation in dem ausgewählten Empfangszweig erfolgt, und des weiteren
• – der Speichereinrichtung 156 zur Auswahl des Delaywertes bereitgestellt, welcher in dem als optimal ermittelten Empfangszweig gemessen wurde.

The information at the exit 150 becomes

• - Provided to the central controller, which realizes on the basis of this information that the detection of the TCH data of the relevant subscriber station in the selected reception branch takes place, and further
• - the storage device 156 for the selection of the delay value, which was measured in the optimally determined reception branch.

The device 155 transfers the measured values to the storage device 156 , From these measured values, as described above, the value which was determined in the reception branch with the best reception and at the output is selected 157 provided. Said delay value is sent by the base station as feedback information for controlling the start time of the transmissions of the subscriber station to the respective subscriber station.

The Delay control by the measurement in the RACH ensures a start synchronization the subscriber station while the delay control by the measurement at the preamble reception a continuous Synchronization of the subscriber station during the connection state assures, in both cases on the basis of Receive Diversity with Selective Combining.

• – übergibt die entschiedenen Symbole an eine Einrichtung 166 für Deinterleaving und FEC-Dekodierung, an deren Ausgang 167 die TCH-Daten ausgegeben werden, und
• – führt eine SIR-Schätzung durch und gibt das Ergebnis an einem Ausgang 165 aus. Auf Grund dieses Ergebnisses erfolgt von der Basisstation eine Rückinformation zur Steuerung der Sendeleistung der Teilnehmerstation an die jeweilige Teilnehmerstation.

In 12 a device of the base station for receiving a TCH is shown. The demodulated and AD-converted received signals are from the n reception branches 110 ( 9 ) of the RF modules 2 provided to the base station. A selector switch 160 is each with one of the m outputs 117 ( 9 ) of the n reception branches 110 whose number matches the number of code sequences. About the control input 161 becomes the selector switch 160 set and selected one of the received signals. The selection represents a modified Receive Diversity with Selective-Combining, in which the selection is done on the basis of the reception of RACH and preambles, as in the above 10 and 11 described. The selected signal is in the despreading device 162 despreads. At an entrance 163 the despreading device is one of the m code sequences. The despread signal becomes a symbol decider 164 fed. The symbol decision maker

• - Passes the decided symbols to a device 166 for deinterleaving and FEC decoding, at the output 167 the TCH data is output, and
• - Perform an SIR estimate and return the result to an output 165 out. Based on this result, the base station sends back information for controlling the transmission power of the subscriber station to the respective subscriber station.

Reference bibliography

• [1] DE 42 40 249 C1
• [2] DE 100 56 087 B4
• [3] Vahid Tarokh, Hamid Jafarkhani, Robert Calderbank: "Space-Time Block Coding for Wireless Communication: Performance Results ", IEEE Journal on selected Areas in communications, Vol. 3, March 1999
• [4] US 2004/0234003 A1
• [5] US 2002/0118770 A1
• [2003] US 2003/0174782 A1
• [7] WO 03/085877 A1
• [8] WO 99/23766 A2
• [9] US 2002/090035 A1
• [10] WO 03/085837 A1
• [11] WO 03/092206 A1
• [12] WO 03/088503 A1
• [13] US Pat. No. 6,421,327 B1
• [14] US 6,317,410 B1
• [15] US 6,392,988 B1
• [16] US 2003/021352 A1
• [17] US 2003/022635 A1
• [18] WO 02/28043 A2
• [19] WO 2004/002011 A1
• [20] US 6,304,581 B1
• [2001] US 2001/055329 A1
• [22] US 6,038,263 A
• [23] Changjiang Xu, Hongjun Xu, Kyung Sup Kwak: "The Application of Space-Time Codes in CDMA Systems ", Proceedings IEEE VTS 53rd, VTC 2001

1

base station

2

Transmit / receive modules of the base station 1

3

air interface

4

subscriber station

5

interface the base station to the PSTN

6

interface the base station to the Internet

7

PSTN subscriber interface the subscriber station

8th

Ethernet Interface the subscriber station

10

Sending branch of the transmitting / receiving modules 2 the base station

12

splinter

13

Entrance of the splitter 12

14

spreading equipment 1 to n for preamble symbols

15

Input for spreading codes of the spreading devices 14

20

module for FEC coding and interleaving

21

entrance for BCH data

22

demultiplexer

23

Space Time coder

24

spreading device for space-time coded BCH data

25

Input for spreading code for spreading device 24

30

module for FEC coding and interleaving

31

entrance for TCH data

32

spreading device for TCH data

33

Input for spreading code for spreading device 32

34

selector switch

35

Control input for selector switch 34

40

Adder of the RF module 2

41

entrance for preamble data

42

entrance for BCH data

43

Entrances 1..m for TCH data

44

Control input for adders 40

45

Digital to analog converter

46

modulator

47

amplifier

50

Downlink period

51

Timeslot the downlink period

52

preamble

53

broadcast channel

55

traffic channel

56

m superimposed code channels

60

Random Access Channel

61

uplink period

62

Timeslot the uplink period

63

preamble

64

Traffic Channel, linked with preamble 63

65

preamble

66

Traffic Channel, linked with preamble 65

67

preamble

68

Traffic Channel, linked with preamble 67

69

m superimposed code channels the uplink period

74

analog Receiving branch of the RF module of the subscriber station

75

Analog to digital converter

76

splinter

77

despreaders 1 to n for Präambelempfang

78

Input for spreading codes of the despreading devices 77

79

Channel estimator for n channels

80

Outputs 1 to n for estimated complex Channel impulse response

81

output for comparison result the transmitting branches of the base station

85

despreader for BCH reception

86

Input for spreading code of the despreading device 85

87

Space-Time decoder

88

multiplexer

89

deinterleaver and FEC decoder

90

output for BCH data

93

module for TCH reception

94

despreader for TCH reception

95

Input for spreading code of the despreading device 94

96

symbol decision and SIR evaluator

97

output for SIR rating

98

deinterleaver and FEC decoder

99

output for TCH data

110

Receiving branch of the transmitting / receiving modules 2 the base station

111

input amplifier

112

demodulator

113

Analog to digital converter

114

splinter

115

output for preamble data

116

output for BCH data

117

Outputs 1 to m for TCH data

118

control input

122

n Despreading devices for RACH

123

entrance for code sequence of the RACH

128

Facility for maximum Ratio Combining (Maximum Likelihood Procedure)

129

output for RACH data

130

output for signal "best reception branch"

135

Facility for n parallel delay measurements

136

Storage for measured delay values

137

output for selected delay value

142

n Despreading devices for Präambelempfang

143

entrance for preamble code sequence

148

Facility for selective combining

150

output for signal "best reception branch"

155

Facility for n parallel delay measurements

156

Storage for measured delay values

157

output for selected delay value

160

selector switch

161

Control input for selector switch 160

162

despreader for TCH data

163

entrance for TCH code sequence

164

symbol decision

165

output for SIR value

166

Facility for deinterleaving and FEC decoding

167

output for TCH data

Claims (12)

Transmission method for use in a radio communication system, comprising a base station ( 1 ) with a plurality of n, but at least two independent transmission / reception branches, an air interface ( 3 ) and a plurality of subscriber stations ( 4 ), which radio communication system in the air interface with DS CDM / CDMA and an embedded TDM / TDMA and TDD operates and in which the slots formed by the TDM / TDMA in the code channels with preamble symbols are introduced, characterized in that the base station in the downlink data type dependent different Transmit Diversity method used for transmission to the subscriber stations, wherein - for preamble symbols, which are spread with code sequences that do not have to match the code sequences for the subsequent data to be transmitted, OTD (Orthogonal Transmit Diversity) is applied and • in one the preamble symbols are supplied via a splitter to a plurality of spreading devices whose number corresponds to the number n of the transmission branches; in a second method step, the preamble symbols are spread with mutually orthogonal codes, and in a third method step, such spread signals are transmitted via in each case one of the transmission branches, - for in a BCH (Broadcast Channel) to be transmitted data STTD (Space Time Transmit Diversity) is used and • are subjected to the BCH data of a FEC coding and interleaving in a first process step In a second method step, the BCH data is supplied to a demultiplexer which provides signals S1 to Sn at a plurality of outputs whose number corresponds to the number n of the transmission branches; in a third method step, the signals S1 to Sn in an STC; Space time coder), which provides the space-time coded signals T1 to Tn on n outputs, • in a fourth method step, the signals T1 to Tn are spread in n spreading devices with a code sequence identical for all spreading devices, and • in one fifth method step, the thus spread signals via each one of the transmission branch e be emitted, - Traffic data for a subscriber station • in a first step of a FEC coding and interleaving are subjected to, • are spread in a second step with one of the code sequences, In a third method step, the spread signals are switched through from one selector to one of the transmitting devices, and in a fourth method step the signals are emitted via the selected transmitting branch. Method according to claim 1, characterized in that that the Base station the preamble symbols in the transmission branches with the reference carrier phase zero and the same Power and send with a symbol power that is larger as the symbol energy of the other data types, where the increase factor smaller than the number of available code channels in the payload area. Method according to Claims 1 and 2, characterized that the Subscriber station the preamble symbols all transmission branches receives and starting from the a priori known properties of the same Performance and reference carrier phase zero - the for the transmission in the downlink optimal transmission branch of the base station determines what the criterion for the detected power of the received preamble symbols is used, and in a RACH (random access channel) when connecting or in the signaling part of an assigned TCH (Traffic Channel) in the Transmitted connection state to the base station, and - a complex Channel impulse response for determines each of the transmission branches and the determined values to the space-time decoder for use in decoding the transmission of the BCH (Broadcast Channel) passes. Method according to claim 1, characterized in that that - the code sequence for the Spreading of the BCH data is a code sequence from the set of TCH code sequences, and - the BCH code sequence in timeslots without transfer of BCH data as Code sequence for TCH data used becomes. Method according to Claims 1, 3 and 4, characterized that the subscriber station - in a first method step, the received signal in a despreader despread with the BCH code sequence, - in one second step, the despread signal in a space Time decoder decodes, where in the decoding from the preamble reception derived complex channel impulse responses of the n downlink transmission paths and at the n outputs of the decoder the signals S1 to Sn outputs, - in a third method step, the signals S1 to Sn in a multiplexer converts to the original serial data stream, and - in one fourth process step deinterleaving the data stream and Undergoing FEC decoding. Method according to claim 1, characterized in that that the subscriber station - at the Receiving each of its assigned TCH performs a rating of the reception quality, as a criterion the signal-to-noise ratio (SIR, Signal to Interference Ratio) each of the TCHs is used, and - outgoing from the determined SIR values a return information to the controller the transmission power of the respective TCH sends to the base station. Method according to claims 1 and 3, characterized that the Base station for the transfer of Traffic data in the downlink - the Selects transmit branch of the RF module, its receiving branch is the Receive Diversity at the reception of RACH data or preambles the respective subscriber station proves to be optimal, if a return information the subscriber station the one to choose Send branch is not present, and otherwise - by the return information the subscriber station predetermined transmission branch selects which specification priority before the result of Receive Diversity. Method according to claims 1 and 6, characterized that the Base station in the downlink due to the return information of the subscriber station for controlling the transmission power of the subscriber station assigned TCH changes the transmission power of this TCH. Method according to the preamble of claim 1, characterized in that the base station in the uplink uses data type dependent different receive diversity method, wherein - when receiving the RACH • for decoding the content decodes all receiving branches in parallel and the symbol decision on the basis of the phase-corrected addition of all received values is performed (maximum ratio combining), and The reception branch which is optimal for the transmission from the respective subscriber station is determined, for which the detected power in the reception branches is used as a criterion; when receiving preamble symbols, these are decoded in parallel in all reception branches and determines the reception branch which is optimal for the transmission from the respective subscriber station is, for which the detected power is used as a criterion in the reception branches, - when receiving the TCH • the decoding takes place respectively in the reception branch, which was determined a priori for the respective subscriber station by the evaluation of the reception of RACH or preamble symbols as the optimal reception branch and • in the said reception branch makes a determination of the channel power of the transmission of the subscriber station. Method according to claim 9, characterized that in the Uplink in each Timeslot only one participant station one preamble sends and the transmission authorization according to an a priori predetermined Schema in a superframe once each code channel of each timeslot of the uplink period of the TDD is granted. Method according to claim 9, characterized that the Base station in the downlink, starting from the reception of the TCH determined channel power values, a return information to the controller the transmission power of the / the TCH to the respective subscriber station sends. Method according to claim 9, characterized that the base station - at Reception of the RACH and preamble symbols determines in parallel in all reception branches a delay value, the the storage of the reception time of the transmission of the subscriber station of the optimal value, - the result of the measurements stores, - to Determination of for the transfer from the respective subscriber station optimal reception branch the in this branch selects delay value and selects - the like certain delay value as return information for controlling the start time of the broadcasts of the subscriber station sends to the respective subscriber station.