CA2027138A1 - Loudspeaking telephone station including directional microphone - Google Patents

Loudspeaking telephone station including directional microphone

Info

Publication number
CA2027138A1
CA2027138A1 CA2027138A CA2027138A CA2027138A1 CA 2027138 A1 CA2027138 A1 CA 2027138A1 CA 2027138 A CA2027138 A CA 2027138A CA 2027138 A CA2027138 A CA 2027138A CA 2027138 A1 CA2027138 A1 CA 2027138A1
Authority
CA
Canada
Prior art keywords
microphones
loudspeaker
microphone
telephone station
lobe
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA2027138A
Other languages
French (fr)
Other versions
CA2027138C (en
Inventor
John Charles Baumhauer Jr.
Jeffrey Phillip Mcateer
Brian Albert Wittman
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
AT&T Corp
Original Assignee
American Telephone and Telegraph Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by American Telephone and Telegraph Co Inc filed Critical American Telephone and Telegraph Co Inc
Publication of CA2027138A1 publication Critical patent/CA2027138A1/en
Application granted granted Critical
Publication of CA2027138C publication Critical patent/CA2027138C/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
    • H04R1/34—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means
    • H04R1/342—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means for microphones
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/02—Constructional features of telephone sets
    • H04M1/20—Arrangements for preventing acoustic feed-back
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
    • H04M1/62—Constructional arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic
    • H04M9/082—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic using echo cancellers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R27/00—Public address systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00—Details of transducers, loudspeakers or microphones
    • H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
    • H04R1/34—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means
    • H04R1/38—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means in which sound waves act upon both sides of a diaphragm and incorporating acoustic phase-shifting means, e.g. pressure-gradient microphone

Abstract

A loudspeaking telephone station (speakerphone) includes a loudspeaker and one or more microphones within the same housing. The microphones are directional, each having a polar response characteristic that includes a major lobe, one or more side lobes, and nulls between pairs of lobes. The loudspeaker is positioned in the null of the polar response characteristic that resides between the major lobe and an adjacent side lobe. The microphone apparatus is positioned so that its major lobe is aimed in a direction that is generally perpendicular to the direction that the loudspeaker is aimed. Means are provided for increasing the distance between input sound ports of a first-order-gradient (FOG) microphone and thereby improving its sensitivity. A pair of such improved FOG microphones are used in assembling a second-order-gradient microphone. Full duplex operation is achieved when a pair of echo cancelers are added to further reduce the coupling between the transmit and receive directions of the speakerphone.
CA002027138A 1989-12-22 1990-10-09 Loudspeaking telephone station including directional microphone Expired - Lifetime CA2027138C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US07/455,128 US5121426A (en) 1989-12-22 1989-12-22 Loudspeaking telephone station including directional microphone
US455,128 1989-12-22

Publications (2)

Publication Number Publication Date
CA2027138A1 true CA2027138A1 (en) 1991-06-23
CA2027138C CA2027138C (en) 1994-08-16

Family

ID=23807530

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002027138A Expired - Lifetime CA2027138C (en) 1989-12-22 1990-10-09 Loudspeaking telephone station including directional microphone

Country Status (4)

Country Link
US (1) US5121426A (en)
JP (1) JPH0761098B2 (en)
KR (1) KR940006002B1 (en)
CA (1) CA2027138C (en)

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Also Published As

Publication number Publication date
KR940006002B1 (en) 1994-06-30
JPH03293846A (en) 1991-12-25
JPH0761098B2 (en) 1995-06-28
CA2027138C (en) 1994-08-16
KR910013805A (en) 1991-08-08
US5121426A (en) 1992-06-09

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