WO2001067626A1

WO2001067626A1 - Method and device for acquiring channels in a wireless spread spectrum communication system

Info

Publication number: WO2001067626A1
Application number: PCT/US2001/003350
Authority: WO
Inventors: Suzanne Hernandez Dino; Wei Zou; Dean E. Thorson; Muriel A. Christensen
Original assignee: Motorola Inc.
Priority date: 2000-03-09
Filing date: 2001-02-01
Publication date: 2001-09-13
Also published as: KR20010112481A; JP2004538668A

Abstract

Briefly, a wireless communication device (200) includes at least one receiver channel element (212), such as a receiver finger, that receives a non-broadcast channel and a forward pilot signal. The wireless communication device (200) also includes a non-broadcast channel acquisition module (216), such as a suitably programmed processing device, that determines whether the non-broadcast channel can be initially acquired. If the non-broadcast channel cannot be acquired, the non-broadcast channel acquisition module (216) determines if the forward pilot signal associated with the non-broadcast channel is of acceptable quality. This may be based on, for example, an energy level of the pilot signal and symbol error rates of received information, or any other suitable criteria. The non-broadcast channel acquisition module (216) also informs a transmitter, such as a BTS, to increase its transmit power of the non-broadcast channel to facilitate non-broadcast channel acquisition if the forward pilot signal is of acceptable quality prior to a predetermined timeout period. Accordingly, the wireless communication device need not wait for a predetermined timeout period to receive a plurality of acceptable consecutive frames.

Description

METHOD AND DEVICE FOR ACQUIRING CHANNELS IN A WIRELESS SPREAD SPECTRUM COMMUNICATION SYSTEM

Cross Reference to Related Co-pending Application

This is a related application to a co-pending application entitled, "Method and Apparatus for Changing Assignment of Receiver Fingers," having attorney docket no. CE08413R, serial no. 09/552,093, having inventors Dino et al., owned by common assignee, filed on the same date, and hereby incorporated by reference.

Field Of The Invention

The invention relates generally to digital wireless communication systems, and more particularly to methods and apparatus for acquiring channels in a code division multiple access (CDMA) communication system.

Background Of The Invention

Wireless spread spectrum communication systems, such as those described, for example, in 3GPP2 C.S00002-A (CDMA 2000), commonly known as third generation partnership 2 and IS95 TIA/EIA-95-B Mobile Station-Base Station Compatibility Standard for Dual-Mode Spread Spectrum Systems., or any other suitable communication system, typically require a mobile station to suitably acquire a non-broadcast channel so that voice, data or other information may be communicated to or from a mobile station and a base site transceiving station (BTS) or other transmitter. Non-broadcast channels include traffic channels, control channels or any other channels that are not broadcast for other mobile stations. Typically, a mobile station, such as a radiotelephone, Internet appliance, laptop computer, or any other suitable communication device, first attempts to acquire a broadcast pilot channel that it receives from one or more BTS's. A synchronization channel is then typically transmitted by the BTS and received by the mobile station. In addition, overhead paging messages are communicated via a paging channel by the BTS and received by the mobile station. A mobile station may then transmit an origination message to the BTS whereafter the BTS sends a channel assignment message on a paging channel to the mobile station. The channel assignment message includes the assigned channel such as the Walsh code or other suitable spreading code information. The mobile station then attempts to suitably acquire the assigned non-broadcast channel (e.g., traffic channel) based on the channel assignment message. Accordingly, the transition to the non-broadcast channel typically occurs after the channel assignment message. Transitioning to the traffic channel typically requires at least three simultaneous tasks.

For example, the mobile station must set up a decoder and combiner on the assigned channel and wait for a traffic frame. The decoder may include a plurality of RAKE receiver fingers. A searcher (such as a searcher receiver) finds the peak energy of the assigned traffic channel, provides that information to a finger management entity that assigns the spreading code, such as a Walsh code, of the assigned traffic channel to a receiver fmger which is already locked on the existing forward pilot channel. The searcher detects the best peaks in a forward pilot signal, then passes the detected peak information to a fmger management entity that assigns a receiver finger to lock on to the good peak. However, before a receiver fmger can lock on to the commanded signal, the mobile station may not receive a good frame since the traffic channel energy from the BTS may be too low, although the forward pilot energy may be high enough to indicate a good peak. However, existing systems do not attempt to accommodate non-broadcast channel (such as traffic channels and control channels) acquisition techniques to accommodate for these and other problems. Instead, conventional systems typically do not determine why unacceptable acquisition frames have been received but instead only require a mobile station to wait for a set timeout period after which time the mobile station reverts back to a pilot channel acquisition state. In addition, the mobile station begins to transmit a reverse pilot signal to the BTS. When a mobile station transitions to the assigned traffic channel or control channel, the mobile station typically needs to make sure that the communication between the BTS and the mobile station on the assigned channel is steady. According to IS95-Section 6.6.4.2, this occurs if the mobile station receives two consecutive traffic channel frames within a 200 millisecond waiting period. If the mobile station does not receive two consecutive good frames it will keep on waiting for the two consecutive good frames for the 200 milliseconds then return back to a forward pilot channel acquisition substate.

However, waiting for a plurality of consecutive good frames within a predefined waiting period can unnecessarily waste time in acquiring a non- broadcast channel. In addition, with CDMA 2000 type systems, that use a fast closed loop transmit power control scheme, the forward pilot signal energy may not accurately represent traffic channel energy. Fast closed loop power control schemes typically allow a BTS to command a mobile to increase or decrease its transmit power, and also allows the mobile station to inform the BTS to increase or decrease its transmission power. Such closed loop transmit power control schemes can allow, for example, downlink power to be adjusted hundreds of times per second. Accordingly, pilot energy measurements may no longer be an accurate representation of traffic channel energies or control channel energies due to the rapid energy changes induced by fast closed loop power control. For example, where a mobile station sends transmit power control information, such as power control bits (PCB), to a base station every 1.25 milliseconds, this control information can require a base station to increase or decrease traffic channel power, particular traffic channel very often.

Consequently, a need exists for a non-broadcast channel acquisition method and wireless communication device that suitably reduces waiting time for acquiring a channel. In addition, it would be desirable if such methods and communication devices provide a determination of why a good non-broadcast channel frame has not been received.

Brief Description Of The Drawings

FIG. 1 is a block diagram illustrating a wireless spread spectrum communication system that employs the channel acquisition method in accordance with one embodiment of the invention. FIG. 2 is a block diagram illustrating one example of a wireless communication device employing a non-broadcast channel acquisition module in accordance with one embodiment of the invention.

FIG. 3 is a flowchart illustrating one example of a method for acquiring a non-broadcast channel in a wireless spread spectrum communication system in accordance with one embodiment of the invention.

FIG. 4 is a flowchart illustrating one example of a method for acquiring a non-broadcast channel in a wireless spread spectrum communication system in accordance with one embodiment of the invention.

Detailed Description Of The Preferred Embodiment

Briefly, a wireless communication device includes at least one receiver channel element, such as a receiver finger, that receives a non-broadcast channel and a forward pilot signal. The wireless communication device also includes a non-broadcast channel acquisition module, such as a suitably programmed processing device, that determines whether the non-broadcast channel can be initially acquired. If the non-broadcast channel cannot be acquired, the non-broadcast channel acquisition module determines if the forward pilot signal associated with the non-broadcast channel is of acceptable quality. This may be based on, for example, an energy level of the pilot signal and symbol error rates of received information, or any other suitable criteria. The non-broadcast channel acquisition module also informs a transmitter, such as a BTS, to increase its transmit power of the non-broadcast channel to facilitate non-broadcast channel acquisition if the forward pilot signal is of acceptable quality prior to a predetermined timeout period. Accordingly, the wireless communication device need not wait for a predetermined timeout period to receive a plurality of consecutive frames but instead may send transmit power control information to a transmitter to require an increase in power transmission during a non-broadcast channel acquisition procedure.

A method is also disclosed which includes reducing a waiting time for non-broadcast channel acquisition, in response to detection of a bad received frame. This may be done, for example, by determining whether a receiver channel element, such as a receiver finger, is still locked on the forward pilot signal after detection of a bad frame, and if the receiver channel element is still locked on the forward pilot signal, detecting that the pilot energy is acceptable, if the bad frame is still detected, the method includes then informing a transmitter, such as the base site transmitter station, to increase the transmit power of the assigned channel to facilitate channel acquisition during a channel acquisition procedure.

FIG. 1 illustrates a spread spectrum wireless communication system, such as a code division multiple access (CDMA) communication system 100, that includes a plurality of mobile stations 102a-102n in operative communication with one or more base site transceiver stations indicated as base stations 104a-104n. The CDMA communication system 100 transmits and receives spread spectrum signals. For purposes of illustration, and not limitation, the disclosed invention will be described with reference to a CDMA 2000 cellular system as described, for example, in the specification entitled, "Physical Layer Standard for CDMA 2000 Spread Spectrum Systems" (3GPP2 C.S0002-A) Version 55, available at w^r w.3gpp2.org and incorporated herein by reference. However, it will be recognized by one of ordinary skill in the art that the disclosed methods and devices may be applicable to any suitable spread spectrum system. By way of example, mobile station 102a may be operating in a simultaneous voice and data mode. Accordingly, one or more base stations 104-104n may be communicating broadcast forward pilot channel information and non-broadcast channel information (e.g., traffic channels and dedicated control channels) to the mobile station 102a.

The base stations 104a-104n may be base site transceiver stations

(BTS's) or any other suitable base stations that can transmit and receive spread spectrum signals. The mobile station 102a may communicate with a plurality of base stations 104a-104n through downlink (forwardlink) communications 106a-106n which may include broadcast pilot channels, multiple traffic channels, dedicated control channels, or any other suitable information. The mobile station 102 likewise communicates with one or more base stations 104a-104n via uplink communications 108a-108n. Other mobile stations may also communicate to one or more of the base stations, as known in the art.

The mobile station 102a performs a non-broadcast channel acquisition procedure in accordance with the invention. For example, the mobile station 102a determines if it has received a bad frame when a receiver fmger is locked on to the appropriate forward pilot channel. This means, for example, that the pilot energy may be good but the non-broadcast channel information is unacceptable. In this instance, the mobile station will inform the appropriate base station to increase its transmission power of the assigned non-broadcast channel. If the mobile station receives a bad frame, and the associated receiver channel element, such as a receiver fmger, is not locked on to the appropriate forward pilot channel, the mobile station will return back to a pilot channel acquisition substate as further described below.

FIG. 2 is a block diagram illustrating one example of a wireless communication device 200, such as a mobile station, that receives a wireless spread spectrum signal 202. The wireless communication device 200 includes a receiver section 204 and a transmitter section 206. The receiver section 204 includes a radio frequency demodulator stage 208, a pilot searcher 210 (searcher receiver), a plurality of receiver channel elements 212, such as RAKE receiver fingers, a combiner 214, a non-broadcast channel acquisition module 216 and a decoder 218.

The radio frequency demodulator stage 208 performs conventional demodulation as known in the art, on spread spectrum signal 202 and provides a digital output of received spread spectrum signals such as a dedicated control channel, one or more traffic channels, and a pilot channel. This digital output information is shown generally as received channel information 220.

The pilot searcher 210, such as a searcher receiver, as known in the art, is operative to search for energy peaks within a pilot signal to obtain a pilot signal energy profile indicating energy levels and phase information as known in the art. The pilot searcher 210 produces pilot energy 222 such as Ec/Io to obtain a pilot energy per time profile as known in the art. This may provide, for example, an energy per chip indication. The pilot searcher 210 is operative to determine pilot signal phase information and a receiver channel element sample window to assign receiver channel elements 212 in a receive window based on the pilot energy peak window detected by the searcher 210. The receiver channel elements 212 may be a plurality of RAKE receivers that receive control signals from suitable control logic (not shown) as known in the art to control each receiver channel element to receive a spread spectrum signal during a specified time window. Each receiver channel element 212 produces received symbol information 224a and 224b, respectively, which includes received symbol energy on a per channel basis such as energy per symbol per incident received noise power, represented as Es/Ior. Each channel receiver element 212 may receive multiple channels from a given base station if desired. Each of the spread spectrum signals 202 received from the various base stations may include different rate spread spectrum information, for example, one traffic channel that may be deemed a fundamental channel may be used for a voice transmission and may communicate information at a lower rate than a supplemental channel that may be used for data transfer. The received channel information 224a and 224b also includes correlated samples, as known in the art. The combiner 214 suitably combines the outputs from the various receiver channel elements, as known in the art, to provide combined sample outputs per channel at a symbol rate represented as information 226 for the decoder 218. The decoder 218 may be a Viterbi decoder, as known in the art, or any other suitable decoder.

The non-broadcast channel acquisition module 216 may be a suitably programmed processing device such as a microprocessor, DSP, state machine, or any other suitable combination of hardware, software, firmware. Such a processing device may also carry out, for example, operations necessary for the combiner 214, Viterbi decoder 218, or any other suitable function within the receiver, if desired. The non-broadcast channel acquisition module 216 receives the pilot energy 222 and also receives the combined sample outputs per channel 226 to create non-broadcast channel performance and acquisition metrics. The non-broadcast channel acquisition module 216 uses this information to determine if the pilot signals and/or the non-broadcast channels are of sufficient quality to demodulate. The non-broadcast channel acquisition module 216 produces channel acquisition control data 230 that is used to inform a transmitter, such as a transmitting BTS, to increase its transmit power of the assigned non-broadcast channel to facilitate non-broadcast channel acquisition.

In one embodiment, the channel acquisition control data 230 is used to require the transmission of transmit power control information 232, such as a power control bit that is stored in memory 234, to be transmitted by transmitter stage 206 to the base station that is transmitting the assigned non-broadcast channel that the receiver 204 is attempting to acquire.

The transmitting stage 206 includes a radio frequency (RF) transmitter 236, a digital to analog converter 238, transmitter control logic and data formatter 240, and an encoder 242. As known in the art, the encoder 242 receives transmit data 244 for transmission by the RF transmitter 236. The transmitter control logic and data formatter 240 suitably controls the RF transmitter 236 through an analog gain control signal 250 as known in the art and also provides suitable data formatting as required as appropriate by protocol requirements for the given system. The transmitter control logic and data formatter 240 outputs formatted data, and digital gain control information 252 to control the gain of the digital to analog converter 238 as known in the art, and also outputs the transmit power control information 232 to provide fast closed loop power control between the communication device 200 and the associated transmitter, such as the base station.

Each of the receiver channel elements receives a non-broadcast channel and a forward pilot signal, as known in the art. The non-broadcast channel acquisition module determines whether the non-broadcast channel can be initially acquired. This is done by measuring the quality of both the received forward pilot signal and the non-broadcast channel, including but not limited to the ratio of received symbol energy to incident noise power, the error rate of the demodulated symbols, etc. to determine if the waveform can be demodulated accurately. If the non-broadcast channel cannot be acquired, the non-broadcast channel acquisition module 216 determines if the forward pilot signal associated with the assigned non-broadcast channel is of acceptable quality. The quality is determined based on the pilot energy information 222 and the symbol error rate determined from the information 226. The symbol error rate is determined by the Viterbi Decoder 218, which actually calculates a distance metric that measures how far the incoming signal's modulation deviates from a desired waveform as known in the art. If the forward pilot signal is of acceptable quality, based on the pilot energy level and/or symbol error rate or other suitable criteria, the non-broadcast channel acquisition module 216 informs the base station to increase transmit power of the non- broadcast channel to facilitate non-broadcast channel acquisition. The base station is informed to increase its transmit power through the channel acquisition control data 230. The transmitter stage 206 sends the non- broadcast channel transmit power control information 232 by sending, for example, at least one power control bit on a reverse pilot channel in response to receiving the channel acquisition control data 230 by the transmitter control logic 240. Although not required, the non-broadcast channel acquisition module 216 preferably does not generate the channel acquisition control data 230 until it has first rechecked the quality of the forward pilot signal after detection of the bad channel frames and after previously locking onto the pilot channel.

The memory 234 may be any suitable register or any other suitable memory that stores transmit power control information 232 for a transmitter, such as described, for example, in the CDMA 2000 specification incorporated herein by reference.

FIG. 3 illustrates a flowchart of an example of one method for acquiring a non-broadcast channel. The process starts in block 300 by setting up the receiver channel elements 212 and combiner 214 on an assigned non- broadcast channel and waiting for a traffic frame to be received. As shown in block 302, the method includes determining whether an assigned non- broadcast channel can be acquired. This may include, for example, determining whether a plurality of acceptable consecutive non-broadcast channel frames have been detected. As known in the art, the Viterbi Decoder 218 provides an indication of accurate reception of non-broadcast channel frames. As shown in block 304, if a plurality of good consecutive frames have not been detected, the method includes determining if the forward pilot signal is still of acceptable quality. This may be done, for example, by rechecking the quality of the forward pilot signal. This is done by evaluating output from the receiver channel element. As shown in block 306, the method includes determining if the forward pilot signal, after rechecking the quality, is still of acceptable quality. If not, the process includes reacquiring the pilot by the pilot searcher again determining a peak timing window for the particular received pilot signal. However, if a bad frame has been detected, and the pilot signal is of acceptable quality, the method proceeds to block 308 which includes sending the traffic transmit power control information 232 to the base station to instruct the base station to increase the power for the assigned non- broadcast channel. Accordingly, the wireless communication device does not need to wait for a timeout period to occur when it receives bad frames. Instead, it proactively informs a transmitter, such as a base station, to increase its transmit power, for the traffic channel even though the pilot energy is of sufficient quality. In this way, with a rapid power increase occurring, the wireless communication unit may quickly receive a good frame with the appropriate power level in response to sending the transmit power control information during the non-broadcast channel acquisition phase. As shown in block 310, the process effectively continues to attempt to acquire a plurality of consecutive frames. However, if the plurality of consecutive frames are not received within, for example, a timeout window, the reacquisition of the pilot signal will occur. However, during the timeout period, the method includes attempting to have a transmitter increase its transmit power to suitably acquire a non-broadcast channel prior to the end of the predetermined timeout period.

FIG. 4 illustrates in more detail a method for acquiring a non-broadcast channel in accordance with one embodiment of the invention. As shown in block 400, the method includes performing pilot signal acquisition to have the receiver channel elements lock on to an appropriate pilot signal. As shown in block 402, the method includes waiting for a frame from an assigned channel to which at least one of the receiver channel elements is assigned. As shown in block 404, the method includes determining whether a good frame has been received. If a good frame has been received, the process proceeds to block 406 which includes determining whether two consecutive frames have been received. However, any suitable number of consecutive frames may be used to indicate a proper acquisition of a channel. As shown in block 408, if two consecutive frames have been received, the end of the acquisition initialization state is reached and the wireless communication device then proceeds to perform conventional communication with the transmitting station. Referring back to block 406, if only one good frame has been received, the process then continues to determine whether another good frame has been received.

Referring back to block 404, if a good frame has not been received, the method includes rechecking the quality of the forward pilot signal to determine if it is still of a suitable quality, as shown in block 410. Accordingly, if the pilot signal is still locked, meaning that the receiver channel element of interest is still locked on a particular pilot channel, and the method includes determining if transmit power control information (e.g., power control bit) has already been sent to indicate an increase in power, as shown in block 412. For example, the method includes determining whether transmit power control information was sent repeatedly over a period of time. An acquisition transmit power control bit history is maintained during the channel acquisition phase. Sending of a power control bit typically may inform a base station to increase its transmit power by ldB. If the base station has been informed, for example, three times during the channel acquisition phase to increase its power, indicating that the BTS was already told to increase its power, the system will wait for the next frame. In one embodiment, three passes are allowed to require the base station to increase its transmit power three different times. If after the three passes the received frame is still of insufficient quality, the wireless communication device then waits for the timeout to occur and then tries to reestablish locking of the pilot signal.

If the power control bit has already been sent, the method includes detecting whether a good frame has been received. If the channel acquisition control data has not already been sent to require that a power control bit be sent to increase the signal transmit power, the method includes informing the base station on a reverse pilot channel to increase transmission power by sending the transmit power control information 232 to the base station. This is shown in block 414. Accordingly, the method includes evaluating the forward pilot signal prior to determining whether the traffic channel can be acquired, as shown in block 400, and subsequently rechecking the quality of the forward pilot signal, as shown in block 410, if an acceptable number of traffic channel frames have not been detected.

Referring back to block 410, if a good frame has not been received and the pilot signal is not locked, the method includes returning back to the pilot signal acquisition algorithm or phase, as shown in block 416, to reacquire a pilot signal. As shown in block 418, the process then begins when another channel needs to be acquired, for example, after receipt of a channel assignment message.

Referring back to FIG. 2, the wireless communication device may be incorporated in a mobile station, or may be incorporated in a base station, if desired. If it is incorporated in a base station, such as when used, for example, with a base station originated call, similar steps are performed by the base station to obtain channel acquisition. By way of further example, where the wireless communication device is a mobile station that is part of a wireless spread spectrum communication system that includes a base station, the method for acquiring a non-broadcast channel includes receiving, by the mobile station, a channel assignment message from the base station over a paging channel. During this time, the mobile station receives a forward pilot signal associated with at least one non-broadcast channel identified in the channel assignment message. The mobile station assigns a receiver channel element to the assigned channel based on the channel assignment message. The mobile station reduces the waiting time for the non-broadcast channel acquisition in response to detection of a bad non-broadcast channel frame. The mobile station reduces the waiting time for non-broadcast channel acquisition by determining whether the receiver channel element that has been assigned to receive the non-broadcast channel based on the associated pilot channel, is still locked on the forward pilot signal, and if the receiver channel element is still locked on the forward pilot signal, informing a base station to increase transmit power of the assigned channel to facilitate non-broadcast channel acquisition. The method also includes attempting to lock on the forward pilot signal in response to detection of the bad frame, if the receiver channel element is not still locked on the forward pilot signal. (See, for example, FIG. 4) The method also includes indicating that a channel is acquired in response to detecting a plurality of consecutive channel frames.

The above methods and wireless communication device effectively detect a possible reason why non-broadcast channel acquisition was unsuccessful and attempts to inform a transmitter to increase its transmitting power during the non-broadcast channel acquisition procedure and waits for a next frame to be transmitted. This helps a wireless communication unit to reduce unnecessary waiting time to acquire a non-broadcast channel. As noted, the method may be carried out, for example, by a software algorithm on a suitably programmed device, or may be implemented using any other suitable configuration. In addition, the methodology may be used for any suitable channel including forward traffic channels as well as dedicated control channels.

It should be understood that the implementation of other variations and modifications of the invention in its various aspects will be apparent to those of ordinary skill in the art, and that the invention is not limited by the specific embodiments described. It is therefore contemplated to cover by the present invention, any and all modifications, variations, or equivalents that fall within the spirit and scope of the basic underlying principles disclosed and claimed herein.

Claims

Claims What Is Claimed Is:

1. A method for acquiring a non-broadcast channel in a wireless spread spectrum communication system that includes at least one mobile station and at least one base station comprising steps of: determining whether the non-broadcast channel can be acquired by the mobile station; if the non-broadcast channel cannot be acquired, determining if a forward pilot signal associated with the non-broadcast channel is of acceptable quality; and if the forward pilot signal is of acceptable quality, informing the base station to increase transmit power of the non-broadcast channel to facilitate non-broadcast channel acquisition.

2. The method of claim 1 wherein determining whether the non-broadcast channel can be acquired by the mobile station includes determining whether a plurality of acceptable non-broadcast channel frame have been detected by the mobile station.

3. The method of claim 1 including the step of evaluating the forward pilot signal prior to determining whether the non-broadcast channel can be acquired, and wherein the step of determining if the forward pilot signal is of acceptable quality includes rechecking the quality of the forward pilot signal if an acceptable number of non-broadcast channel frames have not been detected.

4. The method of claim 3 wherein the step of informing the base station to increase transmit power includes sending non-broadcast channel transmit power control information to the base station by sending at least one power control bit on a reverse pilot channel based on rechecking of the quality of the forward pilot signal.

5. The method of claim 1 wherein the quality of the forward pilot signal is based on at least one of: pilot energy measurements and a received symbol error rate.

6. A communication device that receives a wireless spread spectrum signal comprising: at least one receiver channel element that receives a non- broadcast channel and a forward pilot signal; and a non-broadcast channel acquisition module, operatively responsive to the received non-broadcast channel to determine whether the non-broadcast channel can be acquired; and if the non-broadcast channel cannot be acquired, operative to determine if the forward pilot signal associated with the non-broadcast channel is of acceptable quality; and if the forward pilot signal is of acceptable quality, operative to inform a transmitter to increase transmit power of the non- broadcast channel to facilitate non-broadcast channel acquisition.

7. The communication device of claim 9 wherein the non-broadcast channel acquisition module determines whether the non-broadcast channel can be acquired by determining whether a plurality of consecutive acceptable non-broadcast channel frames have been detected.

8. The communication device of claim 9 wherein the non-broadcast channel acquisition module evaluates the forward pilot signal prior to determining whether the non-broadcast channel can be acquired, and rechecks the quality of the forward pilot signal if an acceptable number of non-broadcast channel frames have not been detected.

9. The communication device of claim 1 1 including: memory containing non-broadcast channel transmit power control information; and a transmitter, operatively coupled to the non-broadcast channel acquisition module and to the memory, and operative to send the non- broadcast channel transmit power control information by sending at least one power control bit on a reverse pilot channel based on the non- broadcast channel acquisition module rechecking the quality of the forward pilot signal.

10. The communication device of claim 9 wherein the quality of the forward pilot signal is based on at least one of: pilot energy measurements and a received symbol error rate.