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1. 发明专利

JPH0554292B2 失效
公开(公告)号：JPH0554292B2
公开(公告)日：1993-08-12
申请号：JP3881284
申请日：1984-03-02
申请人： FUJITSU LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： YAMASHITA ATSUSHI , KATO TADAYOSHI , KURIHARA HIROSHI , ATSUGI GAKUO , SHOMURA TATSURO
IPC分类号： H04B7/155 , H04B7/24 , H04J3/00 , H04L27/22 , H04L27/227

2. 发明专利

JPH0646013A C/N MEASURING INSTRUMENT 失效
公开(公告)号：JPH0646013A
公开(公告)日：1994-02-18
申请号：JP19988792
申请日：1992-07-27
申请人： FUJITSU LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： MISHIRO TOKIHIRO , TAKENAKA TETSUYOSHI , ONO TAKASHI , SHOMURA TATSURO
IPC分类号： H04B7/15 , G01R29/26 , H04B17/00 , H04B17/336 , H04J1/00 , H04L27/26
摘要： PURPOSE:To perform C/N (signal to noise) measurement free from an influence of IM noise with a simple constitution by performing C/N measurement of only a specific carrier and correcting the C/N based on reception levels of respective carriers. CONSTITUTION:An input signal is divided into carrier components having prescribed frequencies f1 to fn by plural band filters 10 different by center frequencies, and their reception levels C1 to Cn are measured by plural reception level measuring means 12. A C/N measuring means 14 measures C/N of the carrier f1. A correction value calculating means 20 calculates an average value of level differences between the reception level C. of the specific carrier measured by the reception level measuring means 12 and reception levels C2 to Cn of the other carriers and calculates a C/N correction value gamma. A C/N correcting means 22 corrects C/N, namely, C1/N1 measured by the C/N measuring means 14 by the C/N correction value gamma and outputs the result.

3. 发明专利

JPH0661899A AUTOMATIC GAIN CONTROL SYSTEM 失效
公开(公告)号：JPH0661899A
公开(公告)日：1994-03-04
申请号：JP21612692
申请日：1992-08-13
申请人： FUJITSU LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： MISHIRO TOKIHIRO , SHOMURA TATSURO
IPC分类号： H04B7/212 , H04J3/00
摘要： PURPOSE:To attain stable demodulation by using a feedback type automatic gain control means to correct a component fluctuated in common among received fluctuation and using a feedfoward type automatic gain control means to correct individual burst fluctuation. CONSTITUTION:An A/D converter means 1, an accumulation latch means 2 and a product arithmetic operation means 3 form a feedfoward type automatic gain control means, and a feedback type automatic gain control means 6 corrects a component fluctuated in common among received fluctuation components. In this case, a demodulated base band signal received as a burst is converted into a digital signal by a D/A converter means 1, a demodulated synchronization pre-stage signal part in the digital signal is latched in the accumulated latch means 2 and outputs of the means 2 and the conversion means 1 are subject to product arithmetic operation by the means 3 and the result is outputted to obtain a prescribed output amplitude.

4. 发明专利

JPH03139027A TRANSMISSION POWER CONTROL SYSTEM IN SATELLITE COMMUNICATION 失效
公开(公告)号：JPH03139027A
公开(公告)日：1991-06-13
申请号：JP27671789
申请日：1989-10-24
申请人： FUJITSU LTD , NIPPON TELEGRAPH & TELEPHONE
发明人： MISHIRO TOKIHIRO , SHOMURA TATSURO
IPC分类号： H04B7/005
摘要： PURPOSE:To improve the control with simple constitution by measuring directly the input/output characteristic of a satellite repeater. CONSTITUTION:Two pilot signals having a prescribed level difference from the 2-level generator 2d of an earth station 2A are added to a main signal and the resulting signal is fed to the repeater 1a of an artificial satellite 1. A level difference between the two pilot signals is varied with the input/output characteristic of the repeater 1a. The characteristic change is used to detect the level difference of the pilot signals returned from the repeater 1a by a detector 2h, thereby obtaining the input/output operating point of the repeater 1a directly. Then the detected reception difference is used as the control reference of transmission power of the earth station 2A and the transmission power of the earth station 2A is controlled by a variable attenuator 2i so that the reception level difference is always constant, thereby making the output power from the repeater 1a constant at all times.

5. 发明专利

JPH01200841A SYSTEM FOR SWITCHING FREQUENCY 失效
公开(公告)号：JPH01200841A
公开(公告)日：1989-08-14
申请号：JP2518788
申请日：1988-02-05
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： SEKI KAZUHIKO , KAZAMA HIROSHI , SHOMURA TATSURO
IPC分类号： H04J4/00 , H04L5/26
摘要： PURPOSE:To lower a loss probability and to set a communication line with a high using efficiency by switching the oscillation frequency of a frequency variable type frequency oscillation when the number of oscillators which one transmitting and receiving node has is made smaller than the number of frequency divisions of the communication line. CONSTITUTION:Frequency variable type frequency oscillators 11-14 oscillate the signals of arbitrary frequencies by control signals from a frequency control circuit 17, and an oscillator switching circuit 15 selects one of the frequency oscillators 11-14. A frequency converting circuit 16 inputs an IF signal, mixes it with the output signal of the circuit 15, and converts it to an RF signal. By setting the frequencies corresponding to communication channels to the oscillators 11-14 and controlling the circuit 15, the communication line between the transmitting and receiving nodes can be set through the use of all communication channels by the oscillators in the number smaller than the number of the frequency divisions of the communication line. Thus, when the number of oscillators which one transmitting and receiving node has is made smaller than the number of frequency divisions of the communication line, the loss probability can be lowered in comparison with a conventional system, and the communication line can be set with a high line using efficiency.

6. 发明专利

JPS6342447B2 失效
公开(公告)号：JPS6342447B2
公开(公告)日：1988-08-23
申请号：JP2525082
申请日：1982-02-20
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： NISHIDA TAKAYOSHI , KAIZUKA TOSHUKI , INOE TAKEO , TAMAI TOSHIHIKO , SHOMURA TATSURO
IPC分类号： H04B7/005 , H04B7/15

7. 发明专利

JPS581580B2 失效
公开(公告)号：JPS581580B2
公开(公告)日：1983-01-12
申请号：JP11210578
申请日：1978-09-11
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： SHOMURA TATSURO , MORIHIRO YOSHITERU
IPC分类号： H04J13/00

8. 发明专利

JPH01164140A BURST RETRANSMITTING TYPE ERROR CORRECTING SYSTEM 失效
公开(公告)号：JPH01164140A
公开(公告)日：1989-06-28
申请号：JP32149087
申请日：1987-12-21
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： INOKI MASAAKI , KAZAMA HIROSHI , SHOMURA TATSURO
IPC分类号： H04L1/16
摘要： PURPOSE:To reduce the number of times of the retransmission of a burst, and to improve a throughput by not retransmitting the burst again as far as an error is not generated in the same blocks of a data burst having arrived at first and the retransmitted data burst. CONSTITUTION:The data part of the burst is divided into X-pieces of small blocks, and a redandunt bit for error detection is added to each block, and the error is detected for every block, and if the error is detected, the presence of the error is compared for every block between the former data part and the output of the data part of the retransmitted burst after the detection of the error, and the block of no error is selected, and is connected with another, and the data is regenerated. Thus, as far as the error does not exist in the same block in the data, the retransmission of the second time comes unnecessary, and even in a state that the quality of a line is bad and many errors exist, the number of times of the retransmission to result in the fall of the throughput can be reduced, and the line of good quality can be offered.

9. 发明专利

JPS6341251B2 失效
公开(公告)号：JPS6341251B2
公开(公告)日：1988-08-16
申请号：JP21329883
申请日：1983-11-15
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： MORIKURA MASAHIRO , MAKI TAKAYOSHI , SHOMURA TATSURO
IPC分类号： H04L1/02 , H03B21/00 , H03C3/40 , H04B7/15 , H04B7/155 , H04B7/185 , H04B7/212 , H04J3/00

10. 发明专利

JPS581581B2 失效
公开(公告)号：JPS581581B2
公开(公告)日：1983-01-12
申请号：JP11210678
申请日：1978-09-11
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： SHOMURA TATSURO
IPC分类号： H04J13/00

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