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31. 发明专利

JPH11205277A RADIO COMMUNICATION SYSTEM 失效
公开(公告)号：JPH11205277A
公开(公告)日：1999-07-30
申请号：JP189798
申请日：1998-01-07
申请人： TOSHIBA CORP
发明人： SATO KAZUMI , NAMEKATA MINORU
IPC分类号： H04J11/00 , H04W28/06 , H04W72/04 , H04Q7/36
摘要： PROBLEM TO BE SOLVED: To reduce the power consumption while enhancing the utilizing efficiency of a transmission frequency band of an OFDM signal by using number of sub carriers for transmission of information through an outgoing channel more than number of sub carriers for transmission of information through an incoming channel in the radio communication system where information is sent by orthogonal frequency division multiplex(OFDM) signals. SOLUTION: In the radio communication system with a non-symmetry characteristic where OFDM signals are used for transmission, number of sub carriers for transmission of information through an outgoing channel 5 is more than number of sub carriers for transmission of information through an incoming channel 4. In the case of employing a same modulation system for the outgoing channel 5 and the incoming channel 4, a ratio of number of sub carriers of both the channels for transmission of information is selected to be a ratio of transmission rates. The low power consumption and miniaturization of radio terminals 1 and improvement of communication quality of the incoming channel or the like are expected by realizing the radio communication system where the transmission rate of the incoming channel 4 is lower than the transmission rate of the outgoing channel 5 in this way.

32. 发明专利

JPH11103279A RECEIVER AND REPEATING INSTALLATION 失效
公开(公告)号：JPH11103279A
公开(公告)日：1999-04-13
申请号：JP26360797
申请日：1997-09-29
申请人： TOSHIBA CORP
发明人： SATO KAZUMI , NAMEKATA MINORU
IPC分类号： H04N17/00 , H04B7/15 , H04B17/00 , H04B17/23 , H04B17/40
摘要： PROBLEM TO BE SOLVED: To eliminate the trouble of a viewer by informing the viewer of that reception quality is degraded by a propagation environment when reception environment is degraded, and a receiver automatically switches a reception modulation system in accordance with the reception environment thereby degrading the reception quality. SOLUTION: A transmission station transmits the same program through plural modulation systems by hierarchized program information. A reception condition measuring part 4 measures the number of demodulated signal errors detected by an error correcting part 7 and sends it to a reception condition judging part 5. The reception condition judging part 5 discriminates whether the reception conditions are good or not from the number of errors and sends the result to a demodulation range control part 8 and a reception condition information part 6. Based on the quality discriminated result of the reception conditions, the demodulation range control part 8 selectively controls the demodulation range of a demodulation part 3. The reception condition reporting part 6 gives the information on the reception conditions judged by the reception condition judging part 5 or the quality of a program capable of being supplied as the result of demodulation range selection to the viewer with image or voice.

33. 发明专利

JPH1127231A RADIO COMMUNICATION SYSTEM 失效
公开(公告)号：JPH1127231A
公开(公告)日：1999-01-29
申请号：JP17466397
申请日：1997-06-30
申请人： TOSHIBA CORP
发明人： SATO KAZUMI , NAMEKATA MINORU
IPC分类号： H04J11/00 , H04W72/04 , H04Q7/36
摘要： PROBLEM TO BE SOLVED: To minimize a digital signal processing circuit of radio terminals PS1 to PS3. SOLUTION: In this radio communication system in which a base station CS and plural radio terminals PS1 to PS3 radio communicate by an orthogonal frequency division multiple system (OFDM system), the base station CS is equipped with a sub carrier assignment part 1 for assigning the number of sub carrier signals corresponding to the amount of information which a radio terminal PS1 communicates out of all the sub carrier signals that can be assigned to the radio terminals PS1 to PS3 when there is an access request from at least one radio terminal PS1.

34. 发明专利

JPH10257551A TRANSMISSION STATION ARRANGING METHOD 失效
公开(公告)号：JPH10257551A
公开(公告)日：1998-09-25
申请号：JP6146797
申请日：1997-03-14
申请人： TOSHIBA CORP
发明人： NAMEKATA MINORU , SATO KAZUMI
IPC分类号： H04J11/00 , H04W4/06 , H04W16/24 , H04Q7/36
摘要： PROBLEM TO BE SOLVED: To prevent the considerable degradation of reception quality at the time of mobile communication and to provide almost uniform quality inside a service area by arranging plural transmission stations in the almost equal distance from a concentrated area. SOLUTION: The same contents are simultaneously transmitted at the same frequency from transmission stations 1 and 2 for providing information through an orthogonal frequency division multiplex transmission system. Radio waves are received while moving mobile reception terminals 4 and 5 inside a service area 3 of the same frequency network as an area in which the radio waves from the transmission stations 1 and 2 can be received. The transmission stations 1 and 2 are installed so as to be positioned at the almost equal distance from the mobile reception terminal 4 for receiving the radio waves while moving through places in which buildings 6 such as high-rise buildings are irregularly constructed. The same frequency network service area 3 is composed of area 7 to be mainly served by the transmission station 1 and area 8 to be mainly served by the transmission station 2.

35. 发明专利

JPH10107714A RECEIVER 失效
公开(公告)号：JPH10107714A
公开(公告)日：1998-04-24
申请号：JP34977596
申请日：1996-12-27
申请人： TOSHIBA CORP
发明人： SATO KAZUMI , NAMEKATA MINORU
IPC分类号： H04J11/00 , H04B7/08
摘要： PROBLEM TO BE SOLVED: To provide the receiver in which the effect of reception waveform distortion due to Rayleigh fading onto a differential coding modulation signal is relaxed. SOLUTION: Phase difference calculation sections 4-1, 4-2 calculate a phase difference between an input signal to a reception section 3-1 and a signal having been received before a prescribed time, and amplitude ratio calculation sections 5-1, 5-2 calculate an amplitude ratio of the input signal to the reception section 3-1 to a signal having been received before a prescribed time. A weight control section 7 measures power of the input signals to the reception sections 3-1, 3-2, and decides the weight given to the amplitude ratio calculation sections 5-1, 5-2 depending on the measurement result. A synthesis section 8 synthesizes the outputs of the amplitude ratio calculation sections 5-1, 5-2 with the weight decided by the weight control section 7. An output of the synthesis section 8 is given to a differential amplitude shift keying(DASK) demodulation section 9, where the signal is converted into a digital data series. On the other hand, outputs from the phase difference calculation sections 4-1, 4-2 are given to an adder 1, where they are simply synthesized and the result is given to a differential phase shift keying(DPSK) demodulation section 10, in which the sum is converted into a digital data series.

36. 发明专利

JPH08101849A DATA RETRIEVAL SYSTEM 失效
公开(公告)号：JPH08101849A
公开(公告)日：1996-04-16
申请号：JP23817394
申请日：1994-09-30
申请人： TOSHIBA CORP
发明人： NAMEKATA MINORU , SUGAWARA TSUTOMU
IPC分类号： G06F17/30 , G06Q30/02 , G06Q30/06 , G06Q50/00
摘要： PURPOSE: To simplify or abolish manuals attached to individual products and facilitate the retrieval of the manual, and to saves the labor for product information management and user support on a maker side which provides the products by storing information regarding the products such as the manuals in a data base in the form of electronic data, and optionally retrieving them through a network. CONSTITUTION: It is made possible to obtain information characteristic of a product by a bar code reader on a home terminal 2 or in-company terminal 9 connected to the article detailed information data base 6 which stores information regarding products through a data communication network 5 and a trunk data communication network 4. At a retrieval request made through the keyboard, the terminal main body sends retrieval request information out to the trunk data base communication network 4 to access the product detailed information data base 6 according to the information, and obtained article information on a product is displayed on a display unit, so that the information regarding the product can be obtained on a on-line basis in real time.

37. 发明专利

JPH07226783A SAMPLING PHASE SYNCHRONIZATION DEVICE 失效
公开(公告)号：JPH07226783A
公开(公告)日：1995-08-22
申请号：JP1877894
申请日：1994-02-16
申请人： TOSHIBA CORP
发明人： NAMEKATA MINORU , MURAKAMI JUNZO
IPC分类号： H04L27/38 , H04B3/06 , H04J3/06 , H04L7/00 , H04L25/08
摘要： PURPOSE:To allow the sampling phase synchronization device for Viterbi equalizer to provide a sampling timing at which the reliability of a demodulation code demodulated by a Viterbi equalizer is best under a multi-path fading transmission line environment specific to mobile communication. CONSTITUTION:A reception signal 13 is orthogonally transformed by an orthogonal transform section 15 in a receiver 14 and becomes a complex base band signal 16. The complex base band signal is given to an oversampling section 17, in which the signal becomes a discrete signal series 18. The discrete signal series 18 is inputted to a transmission line impulse response estimate section 114, in which a transmission line impulse response 115 is estimated. A normalized undesired signal power 117 is calculated by the transmission line impulse response 115 and an average normalized undesired signal power 121 is calculated in addition to the normalized undesired signal power 117. Thus, the average normalized undesired signal power is calculated, an optimum sampling reference signal 123 is decided, the complex base band discrete reception signal series 110 subjected to oversampling is thinned and the result is inputted to the Viterbi equalizer.

38. 发明专利

JPH04274611A EQUALIZING SYSTEM 失效
公开(公告)号：JPH04274611A
公开(公告)日：1992-09-30
申请号：JP3639091
申请日：1991-03-01
申请人： TOSHIBA CORP
发明人： SERIZAWA MUTSUMI , NAMEKATA MINORU
IPC分类号： H04B3/10 , H03H15/00 , H03H17/00 , H03H21/00 , H04B7/005 , H04L25/03
摘要： PURPOSE:To improve the followup ability of a system to high speed fluctuation of the characteristic of a transmission line by implementing both forward equalization and backward equalization and deciding one of them according to an evaluation function. CONSTITUTION:A reception signal is subjected to frequency conversion by an oscillator 1, a mixer 2 and an LPF 3, sampled by a sampler 12 to become a signal series. The series is inputted to an equalizer 4 and an evaluation function calculating means 5 and inputted to a memory 6. Output of the equalizer 4 and the calculating means 5 are stored in memories 10A, 10B. On the other hand, the signal inputted to the memory is inputted to an equalizer 7 and an evaluation function calculating means 8 while being read in the opposite sequence to the input sequence and the output of the equalizer and the evaluation function are calculated and stored once in memories 10C, 10D. Then either of the output of the equalizer 4 and the output of the equalizer 7 is selected and outputted according to the evaluation function with comparing and selecting section 9.

39. 发明专利

JPH04207530A SATELLITE COMMUNICATION SYSTEM AND FREQUENCY TRACKING LOOP 失效
公开(公告)号：JPH04207530A
公开(公告)日：1992-07-29
申请号：JP33562590
申请日：1990-11-30
申请人： TOSHIBA CORP
发明人： SOEYA MIYUKI , SERIZAWA MUTSUMI , OGURA KOJI , NAMEKATA MINORU
IPC分类号： H04L23/00 , H04B7/15
摘要： PURPOSE:To eliminate a frequency offset due to a doppler shift by providing a frequency offset estimate means and a frequency offset correction means to the system. CONSTITUTION:The system is provided with a frequency offset estimate means 11 estimating a frequency offset between a circulating satellite and a mobile body and a frequency offset correction means 13 correcting the estimated frequency offset to a communication signal between the circulating satellite and the mobile body. Since the frequency offset between the circulating satellite and the mobile body is estimated and the estimated frequency offset is corrected to a communication signal between the circulating satellite and the mobile body, the effect of the frequency offset due to a doppler shift is eliminated.

40. 发明专利

JPH03177136A DEMODULATOR DEVICE 失效
公开(公告)号：JPH03177136A
公开(公告)日：1991-08-01
申请号：JP31706589
申请日：1989-12-06
申请人： TOSHIBA CORP
发明人： NAMEKATA MINORU , OGURA KOJI , SERIZAWA MUTSUMI , SAKAKIBARA KATSUMI
IPC分类号： H04L27/01 , H03H17/00 , H04B3/04 , H04B3/06
摘要： PURPOSE:To shorten the measuring time of a code error rate to be used as a threshold by calculating the rates of discordance of the codes of the outputs of a first and a second demodulating means, and selecting a demodulated signal on the basis of this result. CONSTITUTION:A code comparator 106 measures the rate D of dicordance between the code of the output from the first demodulating part 102 and the code of the output from the second demodulating part 104 for a predetermined period. Then, the code comparator 106 compares this discordance rate D with the predetermined discordance rate Dc, and if D>Dc, it decides that the code error rate of the output of the first demodulating part 102 is better than the code error rate of the output of the second demodulating part 104, and selects the output of the first demodulating part 102. On the other hand, if D

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