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71. 发明专利

JP2608645B2 失效
公开(公告)号：JP2608645B2
公开(公告)日：1997-05-07
申请号：JP12413291
申请日：1991-05-29
IPC分类号： H03D5/00 , H04B3/06 , H04L27/01

72. 发明专利

JPH0637664A RECEIVER 失效
公开(公告)号：JPH0637664A
公开(公告)日：1994-02-10
申请号：JP32365791
申请日：1991-11-12
申请人： PHILIPS NV
发明人： GERARUDOUSU KURISUTEIAN MARIA , RUDEII YOHAN FUAN DERU PURATSU
IPC分类号： H04B1/26 , H03B23/00 , H03B28/00 , H03D1/22 , H03D3/00 , H03D5/00 , H03D7/00 , H04B1/30 , H04N5/44
摘要： PURPOSE: To provide a new receiver for RF radio broadcasting or TV broadcasting. CONSTITUTION: An analog signal modulating the carrier frequency of a first sampling frequency is digitally sampled in an A/D converter 5. The receiver is provided with the A/D converter which is continuously connected to a digital right angle phase mixer stage for shifting the carrier frequency of a modulated signal which is digitized, a digital filter device 6 for selection the right angle phase signal and lowering the first sampling frequency to a second sampling frequency and a digital demodulator. The digital right angle phase mixer stage has first Cordic 9. The Cordic has first signal input terminals 16 and 17 and a phase signal input terminal 18. A periodical phase signal is added to a phase signal input terminal from a digital sawtooth wave generator SG with respect to the 2π phase rotation of the signal which is added to the first signal input terminal and which has the repetitive frequency equal to the size of the shift of the carrier frequency.

73. 发明专利

JPH0621759A SIGNAL LEVEL DETECTING CIRCUIT 失效
公开(公告)号：JPH0621759A
公开(公告)日：1994-01-28
申请号：JP19600292
申请日：1992-06-30
申请人： SONY CORP
发明人： KATAKURA MASAYUKI , TSURUOKA TATSUYA
IPC分类号： H03D5/00 , H03H11/12
摘要： PURPOSE:To increase the dynamic range of the detectable signal levels without providing a new external capacitor to the output terminal of a filter nor increasing the number of pins of an integrated circuit. CONSTITUTION:The signal component which is extracted out of an input terminal of a buffer amplifier means OP1 that feeds the output back to the input side by a filter means 11 including the means OP1 is supplied to a rectifier means 12. Thus, the DC offset component emerging at the output of the OP1 is deleted by a capacitor C2 of a feedback loop. Therefore, it is possible to increase the dynamic range of the detectable signal levels without using any new external capacitor nor increasing the number of pins of an integrated circuit.

74. 发明专利

JPH05136631A NON-MODULATED SIGNAL DETECTING AND FREQUENCY PULL-IN DEVICE 失效
公开(公告)号：JPH05136631A
公开(公告)日：1993-06-01
申请号：JP32399791
申请日：1991-11-13
申请人： KOKUSAI DENSHIN DENWA CO LTD
发明人： TAKEUCHI YOSHIO , KOBAYASHI HIDEO
IPC分类号： H03D5/00 , G01R23/16 , H03L7/00 , H04L27/22
摘要： PURPOSE:To prevent almost completely the non-modulate signal detection probability from being deteriorated due to the frequency deviation by using the discrete Fourier transformation, detecting the peak of the spectrum component of the frequency corre sponding to the large frequency deviation and detecting the non-modulated signal. CONSTITUTION:To the discrete Fourier transformation, a computing element 1 performs the DFT of an N sample to input an input signal 100 for each sample in the past and obtains a frequency spectrum 101. A maximum value selector 2 selects and outputs a spectrum component 102, in which the electric power becomes maximum, from the spectrum 101. A peak detector 3 finds out the peak time point of the time change of an output 102 of the selector 2 and outputs a peak timing signal 103. A frequency estimating device 4 obtains the frequency value and a phase value 104 of the non- modulated signal by using the spectrum at the time of the peak. A frequency corrector 5 receives a signal 104 from the estimating device 4, corrects the frequency or the frequency and the phase of the input signal 100 and outputs a frequency correction output 105. As this result, the non-modulated signal detection probability by the frequency deviation does not deteriorate.

75. 发明专利

JPH04265001A AM DETECTING FM DEMODULATING CIRCUIT 失效
公开(公告)号：JPH04265001A
公开(公告)日：1992-09-21
申请号：JP4553491
申请日：1991-02-20
申请人： IWATSU ELECTRIC CO LTD
发明人： KAWASHIMA HIROYUKI , FUJIMOTO ATSUSHI
IPC分类号： H03D5/00
摘要： PURPOSE:To obtain an FM demodulating signal without generating the inversion of a code by detecting the code inversion part of the FM demodulating signal whose code is inverted partially, inverting furthermore the code in the code inversion part and obtaining a final FM demodulating signal. CONSTITUTION:First of all, by detecting all the maximum and the minimum points of an input signal S1(t) of an AM detecting FM demodulating circuit, and inverting the code of an output signal of a cosine/sine absolute value converting circuit for constituting an FM demodulating circuit 3, in the maximum and the minimum points of S1(t), an FM demodulating signal S4(t) whose code is inverted partially is obtained. Subsequently, in a code inversion circuit 4, the code inversion part of the FM demodulating signal S4(t) whose code is inverted partially is detected, and in the code inversion part, the code of S4(t) is furthermore inverted and a final FM demodulating signal S16(t) is obtained. In such a'' v probability of a code error of the FM demodulating signal S16(t) can be made extremely small.

76. 实用新型

JPH0450985U 失效
公开(公告)号：JPH0450985U
公开(公告)日：1992-04-28
申请号：JP9340490
申请日：1990-09-05
IPC分类号： H04N5/46 , H03D5/00 , H04B1/26 , H04N5/60

77. 发明专利

JPH041535B2 失效
公开(公告)号：JPH041535B2
公开(公告)日：1992-01-13
申请号：JP1396983
申请日：1983-01-31
申请人： HARADA IND CO LTD
发明人： KUREBAYASHI SHINPEI
IPC分类号： H04B7/08 , H03D5/00 , H04B1/18

78. 发明专利

JPH0327649A DIGITAL DEMODULATOR 失效
公开(公告)号：JPH0327649A
公开(公告)日：1991-02-06
申请号：JP26793089
申请日：1989-10-13
申请人： SHISUTORON DONAA CORP
发明人： JIERARUDO RICHIYAADO NIYUUERU , PURADEIIPU BUHARUDOWAI
IPC分类号： H04L27/00 , G01D5/245 , H03D5/00 , H03H11/04 , H03M1/60 , H04B1/30
摘要： PURPOSE: To obtain a device indicating a base band signal having a large dynamic range by directly demodulating the frequency encoded DSB-SC output signal of a voltage/frequency converter, and obtaining a digital form base signal. CONSTITUTION: A DSB-SC signal on a signal line 40 is amplified by an amplifier 42, and supplied through a signal line 44 to a linear feedback amplifier 46. The device 46 is provided with an adder 48 whose positive input terminal is connected with the signal line 44. The output of the adder 48 is connected with the input of a dynamic shaping circuit network amplifier 50 which amplifies and filters the DSB-SC signal. The output of the amplifier 50 is feedbacked through a feedback signal line 52 to the negative input of the adder 48, and any distortion introduced by the amplifier 50 can be deleted. The amplification and filtering can be a linear process by the above mentioned feedback. The DSB-SC signal is AC connected with the input of a voltage/frequency converter 54, a frequency in proportion to the voltage level of the DSB-SC signal is provided, and this output signal pulse is impressed to an up-down frequency counter 58.

79. 发明专利

JPH0265491A FREQUENCY CONVERSION CIRCUIT FOR COLOR TELEVISION CHANNEL 失效
公开(公告)号：JPH0265491A
公开(公告)日：1990-03-06
申请号：JP17176089
申请日：1989-07-03
申请人： ITT IND GMBH DEUTSCHE
发明人： DEIITOMAA EAHARUTO
IPC分类号： H03D3/06 , H03D5/00 , H04N5/44 , H04N5/60 , H04N9/64 , H04N11/00 , H04N11/24
摘要： PURPOSE: To suppress interference onto a reproduced image by eliminating a quadrature signal error at a correction stage and using a filter means that locates a spurious signal to a frequency range where no communication signal is in existence so as to suppress the spurious signal. CONSTITUTION: An analog in-phase signal (i) and an analog quadrature signal (q) are digitized by A/D converters w1, w2. In this case, a distortion generated in an analog low frequency - IF converter zz is increased further by the two A/D converters w1, w2 and the error is eliminated by an error correction stage cu and corrected signals ik, qk are outputted. Then 1st and 2nd low pass filters t1, t2 locates a spurious signal having been suppressed optimum to 1st and 2nd acoustic channels and generated by a residual quadrature error of an image carrier for a demodulation period is located at an interval of 0.3MHz from the 1st acoustic channel, and an interference suppression filter nv is used to suppress sufficiently the spurious signal without giving effect onto the video signal. Thus, the interference onto the reproduced image is further suppressed.

80. 发明专利

JPS6323691B2 失效
公开(公告)号：JPS6323691B2
公开(公告)日：1988-05-17
申请号：JP7470283
申请日：1983-04-26
申请人： FUJITSU TEN LTD
发明人： OONISHI YOSHE
IPC分类号： H04B1/10 , G11B20/02 , H03D5/00

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