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41. 发明专利

JPH0974369A DIGITAL BIDIRECTIONAL COMMUNICATION HIGH FREQUENCY DEVICE 失效
公开(公告)号：JPH0974369A
公开(公告)日：1997-03-18
申请号：JP22618995
申请日：1995-09-04
申请人： MATSUSHITA ELECTRIC IND CO LTD
发明人： AKATSUKA TERUMOTO , ASAYAMA OSAMU , TOYAMA TSUTOMU
IPC分类号： H04B1/54 , H04L5/16
摘要： PROBLEM TO BE SOLVED: To miniaturize a digital bi-directional communication high frequency device used for a time division multiplex system. SOLUTION: A first input/output terminal 52 connected to an antenna 1, a high frequency switching device 53, a low-noise amplifier 54, a high frequency band-pass filter 55, a mixer 57 connected to the output of a local oscillator 56 and a second input/output terminal 58 are serially connected. Then, since the high frequency band-pass filter 55 and the mixer 57 are shared and used by a transmission system and a reception system by parallelly connecting a power amplifier 59 between the high frequency band-pass filter 55 and the high frequency switching 53, each one of respective circuits is sufficient. Thus, this device is miniaturized.

42. 发明专利

JPH0918380A TIME DIVISION RADIO COMMUNICATION EQUIPMENT 失效
公开(公告)号：JPH0918380A
公开(公告)日：1997-01-17
申请号：JP16199895
申请日：1995-06-28
申请人： KANSAI NIPPON ELECTRIC
发明人： IDA MASAYUKI
IPC分类号： H04B1/44 , H04B1/26 , H04B1/54
摘要： PURPOSE: To evade interference from a transmission circuit to a reception circuit without interrupting the operation of the modulator of the transmission circuit. CONSTITUTION: For modulation in the modulator 13 in the transmission circuit 10, an oscillation frequency set high beforehand is used as a means for suppressing beat interference, frequency modulation is performed and fist intermediate frequency signals f1 are obtained. The first intermediate frequency signals f1 are supplied to a mixer 14 and mixed with channel selection signals f2 generated in a PLL frequency synthesizer 33 and second intermediate frequency signals f3 are obtained. Then, a multiplying amplifier 16 is provided in the poststage of the mixer 14, the second intermediate frequency signals f3 are multiplied and transmission frequency signals f4 are obtained. By the circuit constitution, the same frequencies do not simultaneously coexist between the reception circuit 30 and the transmission circuit 10 and the beat interference does not occur.

43. 发明专利

JPH08307949A PORTABLE COMMUNICATION TERMINAL MACHINE AND ITS COMMUNICATION RE-CONNECTING SYSTEM 失效
公开(公告)号：JPH08307949A
公开(公告)日：1996-11-22
申请号：JP13871495
申请日：1995-05-12
申请人： KYOCERA CORP
发明人： UCHIYAMA TETSUOMI , TSUKANO KOUHEI , MATSUMOTO HIRONORI , MOROKUMA SHOICHI , UEKI YOSHITAKA
IPC分类号： H04B1/54 , H04M1/27 , H04W84/10 , H04W92/18 , H04Q7/38
摘要： PURPOSE: To continue a call again as if communication is not cut by executing a re-calling operation in short time even if communication is cut, automatically making a response again without executing a response operation and re- connecting communication. CONSTITUTION: When a discrimination means 19 discriminates that communication is cut by permitting the user of a portable communication terminal on either a calling-side or an incoming call-side to execute the cut operation of communication, the call is terminated as it is. When the discrimination means 19 discriminates that communication is cut without executing the cut operation, a call control means 20 controls a call means, and the portable communication terminal machine on the calling-side executes the re-calling operation to the portable communication terminal machine of the incoming call-side without accompanying incoming call sound. Thus, the portable communication terminal machine on the incoming call-side, which is re-called, automatically executes a re-response operation so as to re-connect communication even if the response operation by the user is not executed since a response means is controlled by a response control means 21.

44. 发明专利

JPH08298475A FM TRANSMITTER-RECEIVER 失效
公开(公告)号：JPH08298475A
公开(公告)日：1996-11-12
申请号：JP10153695
申请日：1995-04-26
申请人： NEC CORP
发明人： KANEKO TOMOYA
IPC分类号： H04B1/54
摘要： PURPOSE: To use a frequency synthesizer function in common for a VCO(voltage controlled oscillator) used for a local oscillator of an FM modulator in the case of transmission and of a phase locked loop FM demodulation circuit in the case of reception in the FM transmitter-receiver of the time division system using the same radio frequency for the transmission and the reception. CONSTITUTION: A low-pass filter 3 and a high-pass filter 2 are connected in parallel with a control voltage input terminal of a VCO1 used for an FM modulator in the case of transmission and for a local oscillator for a phase locked loop FM demodulator in the case of reception. A frequency control voltage being an output of a phase locked loop frequency synthesizer circuit 8 for varying a carrier frequency branched from the output of the VCO1 is fed to the VCO1 via the low-pass filter 3 and a modulation/demodulation signal is fed to the VCO1 via the high-pass filter 2.

45. 发明专利

JPH08154067A TRANSMITTER/RECEIVER FOR TIME DIVISION TWO-WAY COMMUNICATION 失效
公开(公告)号：JPH08154067A
公开(公告)日：1996-06-11
申请号：JP31607994
申请日：1994-11-28
申请人： KOKUSAI ELECTRIC CO LTD
发明人： FUJISAWA KAZUHIRO
IPC分类号： H04B1/44 , H04B1/54
摘要： PURPOSE: To avoid the interference of an intermediate frequency(IF) step from a transmission system to a reception system at the transmission/reception time of a TDD transmitter/receiver. CONSTITUTION: This device is provided with a second local oscillator 8 and a reception IF mixer 9 in addition to a first local oscillator 5 for applying a first local oscillation frequency to the reception mixer of the reception system and a transmission mixer 6 of the transmission system to which a transmission/ reception sharing antenna 1 is connected while being switched by a switcher 2. A control part 11 controls first and second local oscillation frequencies at the time of reception and transmission so that the frequencies of a reception IF signal (a) and a transmission IF signal (b) can be made different.

46. 发明专利

JPH07321694A COMMUNICATION EQUIPMENT OF TIME-DIVISION MULTIPLEX ACCESS DUPLEX OPERATION SYSTEM 失效
公开(公告)号：JPH07321694A
公开(公告)日：1995-12-08
申请号：JP13825994
申请日：1994-05-27
申请人： ALPS ELECTRIC CO LTD
发明人： YOSHISATO AKIYUKI
IPC分类号： H04B1/54 , H04L5/16
摘要： PURPOSE:To prevent fluctuation in the oscillation frequency of a local oscillator by configurating the communication equipment so as to start supply of drive power to a frequency mixer at the time of the end of a transmission slot and to stop the supply of power after the end of reception slot. CONSTITUTION:A mixer on/off circuit 24 receives a band signal D or E whose level changes from L to H at the end of a transmission slot T1 and starts supply of drive power to mixers 18, 20. Then the circuit 24 receives the band signal D or E whose level changes from H to L after the end of a reception slot R1 to stop supply of drive power to the mixers 18, 20. When a reception slot is started, the input impedance of the mixers is unchanged and fluctuation in the oscillation frequency is prevented and the power consumption is reduced.

47. 发明专利

JPH07131430A REMOTE MAINTENANCE SYSTEM FOR SIMPLEX RADIO MACHINE 失效
公开(公告)号：JPH07131430A
公开(公告)日：1995-05-19
申请号：JP27873093
申请日：1993-11-09
申请人： FUJITSU LTD
发明人： ITO MASABUMI
IPC分类号： H04B1/54 , H04B7/26 , H04B17/00 , H04W24/00
摘要： PURPOSE:To provide the remote maintenance system for simplex radio machine which remotely measures a simplex radio machine without disturbing the actual operation (communication). CONSTITUTION:With respect to the remote maintenance system for simplex radio machine in the simplex radio communication system where a center 100 and a mobile station communicate with each other through a simplex radio machine 900 which is provided in a base station 200 in a remote place and is connected to the center by a line for operation and a line for measurement, the simplex radio machine is provided with a user discrimination signal output part 150 which outputs a signal, which indicates that remote measurement of this simplex radio machine is impossible, at the time of using the simplex radio machine for transmission and reception or for a certain time after the end of the use, and the simplex radio machine is not measured at the time of using the simplex radio machine for transmission or reception and for the certain time after the end of the use.

48. 发明专利

JPH0746783B2 失效
公开(公告)号：JPH0746783B2
公开(公告)日：1995-05-17
申请号：JP20706685
申请日：1985-09-18
IPC分类号： H04B7/15 , H04B1/54 , H04B3/23 , H04B7/015

49. 实用新型

JPH0662648U 失效
公开(公告)号：JPH0662648U
公开(公告)日：1994-09-02
申请号：JP570893
申请日：1993-01-28
IPC分类号： H04B1/40 , H04B1/50 , H04B1/54

50. 发明专利

JPH06177797A TRANSMISSION CONTROL CIRCUIT FOR TDMA COMMUNICATION EQUIPMENT 失效
公开(公告)号：JPH06177797A
公开(公告)日：1994-06-24
申请号：JP35064892
申请日：1992-12-04
申请人： ALPS ELECTRIC CO LTD
发明人： TANEMURA TAKESHI
IPC分类号： H04B1/44 , H03F1/00 , H03F1/02 , H03F3/62 , H03F3/72 , H04B1/04 , H04B1/54 , H04B1/56
摘要： PURPOSE:To control rise and fall characteristic of a driving voltage to be applied to a high frequency amplifier so as to reduce the excess wave to be generated at the time of transmission to the minimum by the TDMA communication equipment. CONSTITUTION:1st and 2nd driving voltages S1 and S2 with dissimilar rise and fall time constants are outputted from a driving voltage ON/OFF circuit B1. The 1st driving voltage S1 is applied to a pre-stage high frequency amplifier circuit A1 and the 2nd driving voltage S2 is applied to a post stage high frequency amplifier circuit A2. The time required to the rise of the driving voltage S1 applied to the pre-stage high frequency amplifier circuit A1 is longer than the time required to the rise of the ON/OFF switching signal S2 applied to the post stage high frequency amplifier circuit A2. The time required to the fall of the signal is shorter than the time required to the fall of the 2nd ON/OFF switching signal S2 applied to the post stage high frequency amplifier circuit A2.

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