WO1995010891A1 - Recepteur pour communications par etalement du spectre - Google Patents
Recepteur pour communications par etalement du spectre Download PDFInfo
- Publication number
- WO1995010891A1 WO1995010891A1 PCT/JP1994/001701 JP9401701W WO9510891A1 WO 1995010891 A1 WO1995010891 A1 WO 1995010891A1 JP 9401701 W JP9401701 W JP 9401701W WO 9510891 A1 WO9510891 A1 WO 9510891A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- circuit
- signal
- signals
- frequency
- output
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
- H04B1/7097—Interference-related aspects
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
- H04B1/7097—Interference-related aspects
- H04B1/711—Interference-related aspects the interference being multi-path interference
- H04B1/7115—Constructive combining of multi-path signals, i.e. RAKE receivers
- H04B1/7117—Selection, re-selection, allocation or re-allocation of paths to fingers, e.g. timing offset control of allocated fingers
Definitions
- the present invention relates to a receiver of a code division multiple access (CDMA) communication method suitable for mobile communication, and more particularly, to a method for transmitting a frequency offset of a local signal with respect to a received wave to a baseband signal region.
- CDMA code division multiple access
- the present invention relates to a spread spectrum communication receiver for which correction is made in the following.
- baseband signal refers to a signal having no carrier signal component. Specifically, on the transmitting side, the signal after primary modulation and the signal after spreading are used as baseband signals, and on the receiving side, the signal after quadrature detection and before despreading, and the signal after despreading. Is a baseband signal. Background technology
- CDMA transmissions are classified into direct spreading (DS) and frequency hopping (FH).
- DS direct spreading
- FH frequency hopping
- the FH method is rarely used at present. This is because in the FH scheme, a sheet Nporu is decomposed into units called chips, force is required to switch to the high speed carrier signals of different frequencies for each chip, the current technique ⁇ 1, the carrier frequency at high speed This is because it is difficult to realize a frequency synthesizer for switching.
- the DS method is usually used. This is because, on the transmitting side, the primary modulation signal modulated by QPSK or the like is spread (second-order modulation) on a wideband signal by a spreading code, then transmitted on a carrier, and after the receiving side, after removing the carrier, The primary modulation signal is extracted by despreading the wideband signal using the same spreading code as the transmitting side.
- Secondary demodulation is a method of obtaining the original signal by performing primary demodulation.
- the current mobile communication base station equipment has a highly stable reference oscillator, and the national standard for digital car phones is less than 0.05 ppm in absolute accuracy.
- a temperature-compensated crystal oscillator (TCXO) is usually used.
- the frequency accuracy of this crystal oscillator is about 3 ppm in absolute accuracy in the 800 MHz band. Therefore, the frequency of the local signal of the mobile station deviates from the center frequency of the transmitted signal of the base station (that is, the received signal of the mobile station).
- An AFC (Automatic Frequency Control) circuit is required to compensate for this frequency shift and perform stable reception. Furthermore, since the mobile station is generally moving with respect to the base station, the center frequency of the received signal changes by the Doppler frequency.
- FIG. 1 shows a main part of a conventional CDMA receiver having an AFC circuit.
- the intermediate frequency (IF) received signal applied to the input terminal 10 is divided into two by a hybrid coil 1 OA and supplied to a quadrature detector 11.
- the quadrature detector 11 detects an IF reception signal based on a local signal from the voltage controlled oscillator (V C0) 12 and outputs an in-phase baseband signal I and a quadrature baseband signal Q.
- These baseband signals are baseband signals spread by a spreading code.
- the I baseband signal is supplied to an AZD converter 15 via an LPF (one-pass filter) 13 and converted into a digital signal.
- the Q baseband signal is supplied to the AZD converter 16 via the LPF 14 and is converted into a digital signal.
- a correlation detector 17 such as a matched filter or a sliding correlator, to detect a correlation with a spreading code and despread. That is, the correlation detector 17 functions as a despreading circuit and outputs a baseband signal corresponding to the primary modulation signal.
- the output of the correlation detector 17 is a rake demodulator 18 Supplied to Rake demodulator 18 demodulates a baseband signal corresponding to the primary modulation signal and outputs an original signal.
- the AFC circuit 20 is configured as follows.
- the output of the censorship detector 17 is supplied to the delay detection circuit 21.
- the signal detected by the delay detection is supplied to the phase error detection circuit 22.
- the phase error detection circuit 22 calculates and outputs a phase error component t an — I (Q / I) from the amplitudes of the I and Q signals.
- This is a signal representing a phase rotation component on the receiving side, that is, a phase error, based on the mapping point of the primary modulation signal on the transmitting side.
- a phase error signal proportional to the frequency error between the received signal and the local signal is obtained.
- This phase error signal is averaged by the loop filter 23, and is fed back to the VC 02 as a control pressure. In this way, V CO 12 is feedback-controlled with an error correction voltage corresponding to the phase error, and the error between the center frequency of the received signal and the frequency of the local signal is corrected.
- an object of the present invention is to provide a spread spectrum communication receiver which is suitable for the IC scanner and can be reduced in cost.
- the spectrum spread communication receiver comprises:
- a despreading circuit that despreads the first baseband signal using a spreading code and outputs a second baseband signal corresponding to a primary modulation signal on the transmission side;
- a correction circuit that corrects the second baseband signal with a correction signal, and suppresses an interference wave component in the third baseband signal output from the correction circuit.
- an interference elimination circuit for extracting only the desired wave component
- a remodulation circuit that modulates the desired wave component and generates a remodulation signal corresponding to the primary modulation signal on the transmission side;
- the complex conjugate signal of the remodulated signal is multiplied by the baseband signal of ⁇ 2, and a frequency offset component representing an offset frequency corresponding to a deviation of the frequency of the local signal from the center frequency of the received signal is obtained.
- a multiplying circuit for outputting a signal including
- An averaging circuit that averages the output of the multiplication circuit to remove the noise component, and outputs the frequency offset component
- a correction signal generation circuit that extracts the offset frequency from the frequency offset component and generates the correction signal
- the correction signal generation circuit includes a fast Fourier transform circuit that performs a Fourier transform of the frequency offset component, a peak detection circuit that detects a peak of an output of the fast Fourier transform circuit, and an oscillation at a frequency corresponding to the peak. And a digital voltage controlled oscillator for generating the correction signal.
- the interference cancellation circuit may include an adaptive RAKE circuit.
- the spectrum spread communication receiver further comprises:
- a storage circuit for storing a pattern of a known synchronization word
- a detection circuit for detecting the start of reception of the synchronization word from the second baseband signal
- the detection unit detects the synchronization word from the storage circuit.
- the detection circuit detects the end of reception of the synchronization word, the detection circuit outputs the output of the interference removal device.
- a selection circuit for selectively supplying the re-modulation circuit.
- the offset between the center frequency of the received signal and the frequency of the local signal is provided. Can be corrected by digital signal processing in the baseband signal domain. Therefore, it is not necessary to use a high-precision and high-stability oscillator as a local signal oscillator for converting a received signal into a baseband signal. Therefore, the price of the mobile device can be reduced. ⁇ 1] 1 Description of drawing
- FIG. 1 is a block diagram showing a main part of a conventional spread spectrum communication receiver.
- FIG. 2 is a block diagram showing a first embodiment of a spread spectrum communication receiver according to the present invention.
- FIG. 3 is a block diagram showing a second embodiment of the spread spectrum communication receiver according to the present invention.
- FIG. 2 is a block diagram showing a first embodiment of a spread spectrum communication receiver according to the present invention.
- R is the amplitude of the baseband signal S1
- ⁇ is the frequency offset between the received signal and the local signal
- 0 ( ⁇ ) is the phase of the modulation component of the baseband signal S1
- N (t) is the random thermal noise.
- This signal S1 is corrected by the correction circuit 25 by multiplying it by a correction signal S2 described later.
- the corrected signal S3 is supplied to an adaptive RAKE circuit 30 functioning as an interference canceller.
- the adaptive RAKE circuit 30 includes a sampling circuit 31 for sampling the signal S3, a delay circuit 3 2B—32D for delaying its output by a predetermined time, an output of the sampling circuit 31 and a delay circuit 3 Multiplier 35 A — 35 D that multiplies each output of 2 B-32 D by tap coefficient a 1-a 4, output of sampling circuit 31, and output of delay circuit 3 2 B-32 D
- a tap coefficient control circuit 36 that generates tap coefficients a 1 -a 4 based on the output and an output of an adder 39 described later, and an integrating circuit 3 that adds the outputs of the multipliers 35 A—35 D 7, the discrimination circuit 38 that discriminates the addition output S4 and outputs a discrimination output (desired wave component) S5, and the difference between the output S5 of the discrimination circuit 38 and the output S4 of the accumulation circuit 37.
- the discrimination output (desired wave component) S5 is supplied to the inverse modulation circuit 40.
- the inverse modulation circuit 40 has a re-modulation circuit 41 and a multiplication circuit 42.
- the remodulation circuit 41 remodulates the identification output S5 by the same modulation as the primary modulation on the transmission side, and outputs a remodulation signal S6.
- the multiplication circuit 42 multiplies the complex conjugate e-o of the remodulated signal S6 by the input baseband signal S1, and outputs a signal S7. This signal S7 is expressed as follows.
- the inverse modulation circuit 40 separates the baseband signal S 1 into a frequency offset component and a thermal noise component.
- the signal S7 output from the inverse modulation circuit 40 is averaged by the averaging circuit 50 to remove the thermal noise component N (t) ⁇ e ⁇ ⁇ ), and the frequency offset component R′e ' ⁇ ⁇ Only.
- the averaging circuit 50 includes a multiplier 51, an adder 52, a delay circuit 53, and a multiplier 54.
- the multiplier 51 multiplies the signal S 7 by a predetermined constant.
- the adder 52 adds the outputs of the multipliers 51 and 54.
- Delay circuit 53 delays the output of adder 52 by time ⁇ .
- the multiplier 54 multiplies the output of the delay circuit 53 by a constant (1 ⁇ ).
- the averaging circuit 50 averages the signal S7 and outputs a signal S8 including only the frequency offset component of the signal S7.
- the signal S8 is supplied to the frequency analysis circuit 61.
- the frequency analysis circuit 61 is an FFT circuit that performs a Fourier transform on the frequency offset component R ⁇ ezo ⁇ ′. That is, the frequency analysis circuit 61 outputs a signal S9 having a line spectrum at the angular frequency.
- the signal S9 is supplied to a peak detection circuit 62.
- the peak detection circuit 62 obtains an angular frequency ⁇ corresponding to the peak, and supplies a frequency control signal S 10 corresponding to this angular frequency to the digital VC 063.
- the digital VC 063 outputs a correction signal S2 having an angular frequency of ⁇ and a phase opposite to that of the signal S1.
- the correction signal S2 is supplied to the correction circuit 25, and is multiplied by the input baseband signal S1 to remove the frequency offset component of the signal S1.
- Example 2
- FIG. 3 is a block diagram showing a configuration of a main part of a second embodiment of the spread spectrum communication receiver according to the present invention. The difference between the second embodiment and the first embodiment is as follows.
- the synchronization detection circuit 70 detects a reception start point of a frame, that is, a reception start point of a synchronous word, and outputs a switching signal S11.
- receiving the synchronization word Also detects the end of communication.
- a selection circuit 82 that selects and outputs one of the identification output S5 and the synchronization word S12 is provided. This selection is controlled by a switching signal S 11 from the synchronization detection circuit 70.
- sampling circuits 31 A to 31 D are used in place of the sampling circuits 3 ⁇ and the extension circuits 32 B to 32 D in FIG.
- the sampling timings of the sampling circuits 31A to 31D are sequentially shifted as shown in FIG. Thereby, this circuit can also obtain the same result as the combination of the sampling circuit 31 and the delay circuits 32B to 32D in FIG.
- This part may have the same configuration as that of FIG.
- the selection circuit 82 supplies the synchronization word S 12 read out from the synchronization word storage circuit 81 to the remodulation circuit 41 while receiving the synchronization word, while the identification circuit 38 receives the information. Is supplied to the re-modulation circuit 41. In this way, a correct remodulated signal S6 can always be obtained while receiving a known synchronization word. Therefore, the frequency offset component can be removed with higher accuracy than in the first embodiment.
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/448,396 US5594754A (en) | 1993-10-13 | 1994-10-12 | Spread spectrum communication receiver |
DE1994629715 DE69429715T2 (de) | 1993-10-13 | 1994-10-12 | Empfänger für spreizspektrumübertragung |
EP19940929641 EP0675606B1 (en) | 1993-10-13 | 1994-10-12 | Receiver for spread spectrum communication |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP25563393 | 1993-10-13 | ||
JP5/255633 | 1993-10-13 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1995010891A1 true WO1995010891A1 (fr) | 1995-04-20 |
Family
ID=17281465
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP1994/001701 WO1995010891A1 (fr) | 1993-10-13 | 1994-10-12 | Recepteur pour communications par etalement du spectre |
Country Status (6)
Country | Link |
---|---|
US (1) | US5594754A (ja) |
EP (1) | EP0675606B1 (ja) |
JP (1) | JP2764153B2 (ja) |
CN (1) | CN1035586C (ja) |
DE (1) | DE69429715T2 (ja) |
WO (1) | WO1995010891A1 (ja) |
Cited By (2)
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---|---|---|---|---|
US7139307B2 (en) | 2000-08-30 | 2006-11-21 | Matsushita Electric Industrial, Co., Ltd. | Radio receiver |
CN100358247C (zh) * | 1994-11-22 | 2007-12-26 | 三星电子株式会社 | 复扩展电路及扩展方法 |
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE69521852T2 (de) * | 1994-02-10 | 2002-04-04 | Nippon Telegraph & Telephone | Adaptiver spreizspektrumempfänger |
US5696789A (en) * | 1995-03-06 | 1997-12-09 | Unisys Corporation | Apparatus and method for signal identification |
US5692006A (en) * | 1995-07-31 | 1997-11-25 | Qualcomm Incorporated | Adaptive despreader |
JPH09116475A (ja) * | 1995-10-23 | 1997-05-02 | Nec Corp | 時間ダイバーシチ送受信システム |
FI100494B (fi) | 1995-11-20 | 1997-12-15 | Nokia Telecommunications Oy | Menetelmä vastaanottimen ohjaamiseksi ja vastaanotin |
JP3307217B2 (ja) * | 1996-03-01 | 2002-07-24 | 株式会社豊田自動織機 | スペクトラム拡散通信方式における受信装置 |
US6061359A (en) | 1996-08-02 | 2000-05-09 | Golden Bridge Technology, Inc. | Increased-capacity, packet spread-spectrum system and method |
US5805585A (en) * | 1996-08-22 | 1998-09-08 | At&T Corp. | Method for providing high speed packet data services for a wireless system |
US6034987A (en) * | 1996-12-17 | 2000-03-07 | Ericsson Inc. | System for improving the quality of a received radio signal |
WO1998035458A1 (en) * | 1997-02-06 | 1998-08-13 | At & T Wireless Services, Inc. | Method of synchronizing a remote station with a base station in a discrete multitone spread spectrum communications system |
US5943375A (en) * | 1997-02-06 | 1999-08-24 | At&T Wireless Services Inc. | Method to indicate synchronization lock of a remote station with a base station |
JP3563231B2 (ja) * | 1997-04-04 | 2004-09-08 | 株式会社デノン | 周波数制御装置および方法、受信装置、ならびに、通信装置 |
FR2767238B1 (fr) * | 1997-08-07 | 1999-10-01 | Alsthom Cge Alcatel | Dispositifs monocanal et multicanaux de demodulation coherente sans pilote, et ensemble correspondant de reception a plusieurs chemins de diversite |
JP3380446B2 (ja) * | 1997-10-20 | 2003-02-24 | 株式会社鷹山 | Cdma通信システム用受信装置 |
JP3316744B2 (ja) | 1997-10-30 | 2002-08-19 | 三菱電機株式会社 | Afc回路、それを備えた受信機、及び自動周波数制御通信システム |
US5955986A (en) * | 1997-11-20 | 1999-09-21 | Eagle Eye Technologies, Inc. | Low-power satellite-based geopositioning system |
US6366607B1 (en) | 1998-05-14 | 2002-04-02 | Interdigital Technology Corporation | Processing for improved performance and reduced pilot |
US6289061B1 (en) * | 1998-09-24 | 2001-09-11 | Sharp Laboratories Of America, Inc. | Wideband frequency tracking system and method |
JP3031355B1 (ja) | 1998-10-01 | 2000-04-10 | 日本電気株式会社 | 移動局および移動局におけるafc制御方法 |
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US6278725B1 (en) | 1998-12-18 | 2001-08-21 | Philips Electronics North America Corporation | Automatic frequency control loop multipath combiner for a rake receiver |
US6169514B1 (en) | 1999-02-04 | 2001-01-02 | Eagle Eye Technologies, Inc. | Low-power satellite-based geopositioning system |
US7319686B1 (en) * | 1999-03-18 | 2008-01-15 | Industrial Technology Research Institute | Frame synchronization in multi-cell systems with a data interface |
US6560536B1 (en) | 1999-07-12 | 2003-05-06 | Eagle-Eye, Inc. | System and method for rapid telepositioning |
US8255149B2 (en) | 1999-07-12 | 2012-08-28 | Skybitz, Inc. | System and method for dual-mode location determination |
US6480788B2 (en) * | 1999-07-12 | 2002-11-12 | Eagle-Eye, Inc. | System and method for fast acquisition reporting using communication satellite range measurement |
US20040143392A1 (en) | 1999-07-12 | 2004-07-22 | Skybitz, Inc. | System and method for fast acquisition reporting using communication satellite range measurement |
US6208842B1 (en) * | 1999-09-30 | 2001-03-27 | Motorola Inc. | Method and apparatus for estimating a channel parameter |
US6608858B1 (en) * | 2000-01-26 | 2003-08-19 | Qualcomm Incorporated | Multipath doppler adjusted frequency tracking loop |
CA2652083A1 (en) | 2000-03-28 | 2001-10-04 | Interdigital Technology Corporation | Cdma system which uses pre-rotation before transmission |
AU2001283181A1 (en) | 2000-08-09 | 2002-02-18 | Skybitz, Inc | System and method for fast code phase and carrier frequency acquisition in gps receiver |
AU2001288963A1 (en) | 2000-09-18 | 2002-04-02 | Skybitz, Inc | System and method for fast code phase and carrier frequency acquisition in gps receiver |
US7443826B1 (en) | 2000-10-04 | 2008-10-28 | Telefonaktiebolaget L M Ericsson (Publ) | Method and apparatus for automatic frequency control in a CDMA receiver |
GB2369275B (en) | 2000-11-21 | 2004-07-07 | Ubinetics Ltd | A rake receiver and a method of providing a frequency error estimate |
JP3835800B2 (ja) * | 2002-02-08 | 2006-10-18 | 株式会社東芝 | 受信フレームの同期方法、および、受信装置 |
US6741665B2 (en) * | 2002-06-20 | 2004-05-25 | Nokia Corporation | Method and apparatus providing an amplitude independent automatic frequency control circuit |
EP1383239A1 (fr) * | 2002-07-17 | 2004-01-21 | STMicroelectronics N.V. | Procédé et dispositif de contrôle automatique de la fréquence dans un récepteur du type DS-CDMA |
FR2843249A1 (fr) * | 2002-07-31 | 2004-02-06 | Koninkl Philips Electronics Nv | Recepteur comportant des moyens de reception multiples en parallele. |
US7301993B2 (en) * | 2002-09-13 | 2007-11-27 | Broadcom Corporation | Channel estimation in a spread spectrum receiver |
US7483479B2 (en) * | 2004-09-16 | 2009-01-27 | Keyeye Communications | Scaled signal processing elements for reduced filter tap noise |
EP1681773A1 (en) * | 2005-01-13 | 2006-07-19 | Centre National D'etudes Spatiales | Spread spectrum signal |
CN1317830C (zh) * | 2005-04-15 | 2007-05-23 | 展讯通信(上海)有限公司 | 自动频偏校正方法及使用该方法的装置和接收机 |
US7421252B2 (en) * | 2005-08-02 | 2008-09-02 | Freescale Semiconductor, Inc. | Center frequency control of an integrated phase rotator band-pass filter using VCO coarse trim bits |
JP5083713B2 (ja) * | 2005-10-03 | 2012-11-28 | 日本電気株式会社 | 等化器を含む信号受信装置、端末装置、信号受信方法および信号受信プログラム |
US8229041B2 (en) | 2009-05-26 | 2012-07-24 | Broadcom Corporation | Direct detection of wireless interferers in a communication device for multiple modulation types |
US8743848B2 (en) | 2009-05-26 | 2014-06-03 | Broadcom Corporation | Hybrid location determination for wireless communication device |
US9503139B2 (en) | 2013-08-06 | 2016-11-22 | Motorola Solutions, Inc. | Very low intermediate frequency (VLIF) receiver and method of controlling VLIF receiver |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH02165746A (ja) * | 1988-12-20 | 1990-06-26 | Mitsubishi Electric Corp | ダイレクトシーケンス復調装置 |
JPH0621915A (ja) * | 1992-06-29 | 1994-01-28 | Mitsubishi Electric Corp | Afc回路 |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4841544A (en) * | 1987-05-14 | 1989-06-20 | The Charles Stark Draper Laboratory, Inc. | Digital direct sequence spread spectrum receiver |
US5150377A (en) * | 1990-11-02 | 1992-09-22 | At&T Bell Laboratories | Direct sequence spread spectrum (dsss) communications system with frequency modulation utilized to achieve spectral spreading |
US5218619A (en) * | 1990-12-17 | 1993-06-08 | Ericsson Ge Mobile Communications Holding, Inc. | CDMA subtractive demodulation |
US5467367A (en) * | 1991-06-07 | 1995-11-14 | Canon Kabushiki Kaisha | Spread spectrum communication apparatus and telephone exchange system |
US5271034A (en) * | 1991-08-26 | 1993-12-14 | Avion Systems, Inc. | System and method for receiving and decoding global positioning satellite signals |
KR950009406B1 (ko) * | 1992-11-27 | 1995-08-22 | 삼성전자주식회사 | 코드분할 다중접근(cdma) 직접확산(ds) 방식 수신기의 클럭 복구안정화방법 및 회로 |
-
1994
- 1994-10-12 CN CN94190783A patent/CN1035586C/zh not_active Expired - Fee Related
- 1994-10-12 DE DE1994629715 patent/DE69429715T2/de not_active Expired - Lifetime
- 1994-10-12 US US08/448,396 patent/US5594754A/en not_active Expired - Lifetime
- 1994-10-12 WO PCT/JP1994/001701 patent/WO1995010891A1/ja active IP Right Grant
- 1994-10-12 JP JP51158795A patent/JP2764153B2/ja not_active Expired - Fee Related
- 1994-10-12 EP EP19940929641 patent/EP0675606B1/en not_active Expired - Lifetime
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH02165746A (ja) * | 1988-12-20 | 1990-06-26 | Mitsubishi Electric Corp | ダイレクトシーケンス復調装置 |
JPH0621915A (ja) * | 1992-06-29 | 1994-01-28 | Mitsubishi Electric Corp | Afc回路 |
Non-Patent Citations (1)
Title |
---|
See also references of EP0675606A4 * |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN100358247C (zh) * | 1994-11-22 | 2007-12-26 | 三星电子株式会社 | 复扩展电路及扩展方法 |
US7139307B2 (en) | 2000-08-30 | 2006-11-21 | Matsushita Electric Industrial, Co., Ltd. | Radio receiver |
Also Published As
Publication number | Publication date |
---|---|
EP0675606A1 (en) | 1995-10-04 |
DE69429715D1 (de) | 2002-03-14 |
EP0675606A4 (en) | 1997-05-21 |
CN1115590A (zh) | 1996-01-24 |
EP0675606B1 (en) | 2002-01-23 |
JP2764153B2 (ja) | 1998-06-11 |
US5594754A (en) | 1997-01-14 |
DE69429715T2 (de) | 2002-08-08 |
CN1035586C (zh) | 1997-08-06 |
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