CA2385111A1 - Signal acquisition system for spread spectrum receiver - Google Patents
Signal acquisition system for spread spectrum receiver Download PDFInfo
- Publication number
- CA2385111A1 CA2385111A1 CA002385111A CA2385111A CA2385111A1 CA 2385111 A1 CA2385111 A1 CA 2385111A1 CA 002385111 A CA002385111 A CA 002385111A CA 2385111 A CA2385111 A CA 2385111A CA 2385111 A1 CA2385111 A1 CA 2385111A1
- Authority
- CA
- Canada
- Prior art keywords
- matched filter
- samples
- correlation
- signal
- sampling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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
- H04B1/7073—Synchronisation aspects
- H04B1/7075—Synchronisation aspects with code phase acquisition
- H04B1/708—Parallel implementation
-
- 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
- H04B1/709—Correlator structure
- H04B1/7093—Matched filter type
Abstract
The invention relates to a device detecting a demodulated signal received by a spread spectrum receiver and converted into digital samples.
The device is characterized by comprising a matched filter (4-16) for calculating the correlation between an incoming signal and at least one reference signal; an oscillator (4-8) for generating a sampling frequency;
a sampling circuit (4-10) for re-sampling said demodulated digital sample signal at said sampling frequency, which is such that the timing of samples of the reference signals of the matched filter (4-16) corresponds to the timing of a sample signal going from the sampling circuit to the matched filter (4-16);
and a multiplier (4-12) in which the sample signal is multiplied by a carrier replica generated locally before the sampling circuit or thereafter, to remove the carrier from the sample signal.
The device is characterized by comprising a matched filter (4-16) for calculating the correlation between an incoming signal and at least one reference signal; an oscillator (4-8) for generating a sampling frequency;
a sampling circuit (4-10) for re-sampling said demodulated digital sample signal at said sampling frequency, which is such that the timing of samples of the reference signals of the matched filter (4-16) corresponds to the timing of a sample signal going from the sampling circuit to the matched filter (4-16);
and a multiplier (4-12) in which the sample signal is multiplied by a carrier replica generated locally before the sampling circuit or thereafter, to remove the carrier from the sample signal.
Claims (12)
1. A device for detecting a demodulated signal received by a spread spectrum receiver and converted into digital samples, characterized in that the device comprises:
a matched filter (4-16) for calculating the correlation between an in-coming signal (4-2, 4-4) and at least one reference signal (4-21);
an oscillator (4-8) for generating a sampling frequency;
a sampling circuit (4-10) for re-sampling said demodulated digital sample signal at said sampling frequency, which is such that the timing of samples of a sample signal going from the sampling circuit (4-10) to the matched filter (4-16) corresponds to the timing of the reference signals (4-21) of the matched filter (4-16); and a multiplier (4-12) in which the sample signal is multiplied by a car-rier replica generated locally before the sampling circuit (4-10) or thereafter, to remove the carrier from the sample signal.
a matched filter (4-16) for calculating the correlation between an in-coming signal (4-2, 4-4) and at least one reference signal (4-21);
an oscillator (4-8) for generating a sampling frequency;
a sampling circuit (4-10) for re-sampling said demodulated digital sample signal at said sampling frequency, which is such that the timing of samples of a sample signal going from the sampling circuit (4-10) to the matched filter (4-16) corresponds to the timing of the reference signals (4-21) of the matched filter (4-16); and a multiplier (4-12) in which the sample signal is multiplied by a car-rier replica generated locally before the sampling circuit (4-10) or thereafter, to remove the carrier from the sample signal.
2. A device as claimed in claim 1, characterized in that the sampling frequency generated by said oscillator (4-8) is adjustable such that the timing of a sample signal going from the sampling circuit to the matched filter (4-16) corresponds to the timing of samples of the reference signals of the matched filter (4-16).
3. A device as claimed in claim 1 or 2, characterized in that the device comprises one or more coherent integrators (4-35) for integrating correlation samples (4-26, 4-28) generated as outputs by the matched filter (4-16) over an integration period that is longer than the length in time of the matched filter (4-16).
4. A device as claimed in claim 3, characterized in that the outputs of the matched filter (4-16) are complex correlation samples (4-26, 4-28), and that the coherent integrator (4-35) comprises an accumulator (4-34) for summing up two or more correlation samples (4-26, 4-28) corresponding to the same phase difference of the incoming signal, the sum corresponding to a correlation result calculated with one phase difference and whose integration time is N MF-L c samples, wherein N MF is the length of the matched filter (4-16) in number of samples, and L c is the number of correlation samples summed up by the accumulator (4-34).
5. A device as claimed in claim 1, 2, 3 or 4, characterized in that the device comprises a calculator (4-38) for calculating the absolute val-ues or estimates of the absolute values of the correlation samples given as outputs by the matched filter (4-16) or the coherent integrator (4-35).
6. A device as claimed in claim 5, characterized in that the outputs of the matched filter (4-16) or the coherent integrator (4-35) are com-plex correlation samples, and that said calculator (4-38) calculates the abso-lute value or an estimate of the absolute value of a complex correlation sam-ple.
7. A device as claimed in claim 5 or 6, characterized in that the device comprises one or more non-coherent integrators (4-41) for inte-grating said absolute values or estimates of the absolute values of the correla-tion samples over an integration period that is longer than the length in time of the matched filter (4-16).
8. A device as claimed in claim 7, characterized in that the non-coherent integrator (4-41) comprises an accumulator (4-40) for summing up two or more absolute values or an estimates of the absolute values of a correlation sample corresponding to the same phase difference of the incom-ing signal, the sum corresponding to a correlation result calculated with one phase difference and whose integration time is N MF-L N samples, wherein N MF
is the length of the matched filter (4-16) in number of samples, and L N is the number of correlation samples summed up by the accumulator (4-40).
is the length of the matched filter (4-16) in number of samples, and L N is the number of correlation samples summed up by the accumulator (4-40).
9. A device as claimed in any one of the preceding claims, char-acterized in that the device comprises a comparator (4-45), which com-pares the output values of the matched filter (4-16), the coherent integrator (4-35), the absolute value calculator (4-38) or the non-coherent integrator (4-41) with a predetermined threshold value, and gives a reference result that indi-cates if the output value exceeds or not said threshold value.
10. A device as claimed in claim 9, characterized in that the device comprises a controller for gathering several comparison results corre-sponding to the same phase difference and reference signal, and which, in response to a preset portion of the gathered reference results indicating that the output value exceeds said threshold value, assumes that a signal is found.
11. A device as claimed in any one of the preceding claims, characterized in that the device comprises a controller for adjusting said oscillator to generate a sampling frequency for searching for a correlation at different phase differences of a received signal.
12. A device as claimed in any one of the preceding claims, characterized in that the device is multi-channel and searches time-dividedly in parallel for two or more received signals.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI992210 | 1999-10-13 | ||
| FI19992210 | 1999-10-13 | ||
| FI20002154A FI114887B (en) | 1999-10-13 | 2000-09-29 | Signal detection system of a spread spectrum receiver |
| FI20002154 | 2000-09-29 | ||
| PCT/FI2000/000879 WO2001028116A1 (en) | 1999-10-13 | 2000-10-12 | Signal acquisition system for spread spectrum receiver |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2385111A1 true CA2385111A1 (en) | 2001-04-19 |
| CA2385111C CA2385111C (en) | 2010-02-16 |
Family
ID=26160790
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2385111A Expired - Lifetime CA2385111C (en) | 1999-10-13 | 2000-10-12 | Signal acquisition system for spread spectrum receiver |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US6909739B1 (en) |
| EP (1) | EP1222748B1 (en) |
| JP (1) | JP5059268B2 (en) |
| AT (1) | ATE370555T1 (en) |
| AU (1) | AU770577B2 (en) |
| CA (1) | CA2385111C (en) |
| DE (1) | DE60036010T2 (en) |
| FI (1) | FI114887B (en) |
| WO (1) | WO2001028116A1 (en) |
Families Citing this family (29)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7515896B1 (en) | 1998-10-21 | 2009-04-07 | Parkervision, Inc. | Method and system for down-converting an electromagnetic signal, and transforms for same, and aperture relationships |
| US6061551A (en) | 1998-10-21 | 2000-05-09 | Parkervision, Inc. | Method and system for down-converting electromagnetic signals |
| US7236754B2 (en) | 1999-08-23 | 2007-06-26 | Parkervision, Inc. | Method and system for frequency up-conversion |
| US6813485B2 (en) * | 1998-10-21 | 2004-11-02 | Parkervision, Inc. | Method and system for down-converting and up-converting an electromagnetic signal, and transforms for same |
| US6370371B1 (en) | 1998-10-21 | 2002-04-09 | Parkervision, Inc. | Applications of universal frequency translation |
| US7039372B1 (en) | 1998-10-21 | 2006-05-02 | Parkervision, Inc. | Method and system for frequency up-conversion with modulation embodiments |
| US6879817B1 (en) * | 1999-04-16 | 2005-04-12 | Parkervision, Inc. | DC offset, re-radiation, and I/Q solutions using universal frequency translation technology |
| US6853690B1 (en) | 1999-04-16 | 2005-02-08 | Parkervision, Inc. | Method, system and apparatus for balanced frequency up-conversion of a baseband signal and 4-phase receiver and transceiver embodiments |
| US7065162B1 (en) | 1999-04-16 | 2006-06-20 | Parkervision, Inc. | Method and system for down-converting an electromagnetic signal, and transforms for same |
| US7110444B1 (en) | 1999-08-04 | 2006-09-19 | Parkervision, Inc. | Wireless local area network (WLAN) using universal frequency translation technology including multi-phase embodiments and circuit implementations |
| US7693230B2 (en) | 1999-04-16 | 2010-04-06 | Parkervision, Inc. | Apparatus and method of differential IQ frequency up-conversion |
| US8295406B1 (en) | 1999-08-04 | 2012-10-23 | Parkervision, Inc. | Universal platform module for a plurality of communication protocols |
| FI114887B (en) * | 1999-10-13 | 2005-01-14 | U Nav Microelectronics Corp | Signal detection system of a spread spectrum receiver |
| US7010286B2 (en) | 2000-04-14 | 2006-03-07 | Parkervision, Inc. | Apparatus, system, and method for down-converting and up-converting electromagnetic signals |
| US7010559B2 (en) * | 2000-11-14 | 2006-03-07 | Parkervision, Inc. | Method and apparatus for a parallel correlator and applications thereof |
| US7454453B2 (en) | 2000-11-14 | 2008-11-18 | Parkervision, Inc. | Methods, systems, and computer program products for parallel correlation and applications thereof |
| US6760365B2 (en) * | 2001-10-11 | 2004-07-06 | Interdigital Technology Corporation | Acquisition circuit for low chip rate option for mobile telecommunication system |
| US7072427B2 (en) | 2001-11-09 | 2006-07-04 | Parkervision, Inc. | Method and apparatus for reducing DC offsets in a communication system |
| US7321640B2 (en) * | 2002-06-07 | 2008-01-22 | Parkervision, Inc. | Active polyphase inverter filter for quadrature signal generation |
| US7460584B2 (en) | 2002-07-18 | 2008-12-02 | Parkervision, Inc. | Networking methods and systems |
| US7379883B2 (en) | 2002-07-18 | 2008-05-27 | Parkervision, Inc. | Networking methods and systems |
| WO2004021506A2 (en) * | 2002-08-28 | 2004-03-11 | Zyray Wireless, Inc. | Iterative multi-stage detection technique for a diversity receiver having multiple antenna elements |
| US7312700B2 (en) * | 2005-01-26 | 2007-12-25 | Broadcom Corporation | GPS enabled cell phone with common interest alerts |
| US20070038560A1 (en) * | 2005-08-12 | 2007-02-15 | Carl Ansley | Transaction payment system and processing |
| DE602006010810D1 (en) * | 2006-03-22 | 2010-01-14 | Qualcomm Inc | Broadband frequency discriminator and radio receiver |
| US11174458B2 (en) | 2007-04-23 | 2021-11-16 | Koligo Therapeutics, Inc. | Cell separation apparatus and methods of use |
| DE102007029316B4 (en) * | 2007-06-22 | 2011-02-10 | Volker Schrage | Apparatus for UV radiation hardening |
| US8004863B2 (en) * | 2007-12-26 | 2011-08-23 | Silicon Laboratories Inc. | Circuit device and method of providing feedback across an isolation barrier |
| CN109613334B (en) * | 2018-12-04 | 2022-02-25 | 上海司南卫星导航技术股份有限公司 | Frequency estimation device, terminal and computer readable medium |
Family Cites Families (30)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4785463A (en) * | 1985-09-03 | 1988-11-15 | Motorola, Inc. | Digital global positioning system receiver |
| US5504785A (en) * | 1993-05-28 | 1996-04-02 | Tv/Com Technologies, Inc. | Digital receiver for variable symbol rate communications |
| WO1995010903A1 (en) * | 1993-10-14 | 1995-04-20 | Ntt Mobile Communications Network Inc. | Correlation detector and communication apparatus |
| US5377225A (en) | 1993-10-19 | 1994-12-27 | Hughes Aircraft Company | Multiple-access noise rejection filter for a DS-CDMA system |
| IL111469A0 (en) | 1993-11-01 | 1994-12-29 | Omnipoint Corp | Despreading/demodulating direct sequence spread spectrum signals |
| JPH07297805A (en) * | 1994-04-28 | 1995-11-10 | Toshiba Corp | Method and circuit for synchronizing spread spectrum code |
| JP2682493B2 (en) * | 1995-02-22 | 1997-11-26 | 日本電気株式会社 | Receiver |
| JPH08265216A (en) * | 1995-03-20 | 1996-10-11 | Rohm Co Ltd | Signal processor |
| US5920589A (en) | 1995-06-07 | 1999-07-06 | Sanconix Inc. | Direct sequence spread spectrum DSP system |
| US5640416A (en) * | 1995-06-07 | 1997-06-17 | Comsat Corporation | Digital downconverter/despreader for direct sequence spread spectrum communications system |
| US5654991A (en) * | 1995-07-31 | 1997-08-05 | Harris Corporation | Fast acquisition bit timing loop method and apparatus |
| JPH0964783A (en) * | 1995-08-29 | 1997-03-07 | Canon Inc | Spread spectrum communication equipment |
| JP2926651B2 (en) * | 1995-11-02 | 1999-07-28 | 株式会社鷹山 | Matched filter circuit |
| FR2748571B1 (en) * | 1996-05-09 | 1998-08-07 | Europ Agence Spatiale | RECEIVER DEVICE FOR A NAVIGATION SYSTEM IN PARTICULAR BY SATELLITE |
| GB2315647B (en) | 1996-07-23 | 2001-02-21 | Roke Manor Research | Randomised code acquisition |
| US5715276A (en) | 1996-08-22 | 1998-02-03 | Golden Bridge Technology, Inc. | Symbol-matched filter having a low silicon and power requirement |
| US5809063A (en) * | 1996-10-25 | 1998-09-15 | General Electric Company | Coherent detection architecture for remote calibration of coherent systems using direct sequence spread spectrum transmission of reference and calibration signals |
| US6212246B1 (en) * | 1996-11-21 | 2001-04-03 | Dsp Group, Inc. | Symbol-quality evaluation in a digital communications receiver |
| JP3884115B2 (en) | 1996-12-10 | 2007-02-21 | 三菱電機株式会社 | Digital matched filter |
| EP0855796A3 (en) | 1997-01-27 | 2002-07-31 | Yozan Inc. | Matched filter and filter circuit |
| JP3408944B2 (en) * | 1997-04-24 | 2003-05-19 | シャープ株式会社 | Demodulator in direct spread spectrum communication system and correlator in the same |
| US5999561A (en) | 1997-05-20 | 1999-12-07 | Sanconix, Inc. | Direct sequence spread spectrum method, computer-based product, apparatus and system tolerant to frequency reference offset |
| JP3751419B2 (en) * | 1997-06-16 | 2006-03-01 | 松下電器産業株式会社 | Matched filter and synchronization method |
| JP3380446B2 (en) * | 1997-10-20 | 2003-02-24 | 株式会社鷹山 | Receiver for CDMA communication system |
| DK0924532T3 (en) | 1997-11-19 | 2006-07-17 | Imec Vzw | Method and apparatus for receiving GPS / GLONASS signals |
| JPH11186984A (en) * | 1997-12-18 | 1999-07-09 | Sony Corp | Correlation detector and correlation detection method |
| JP3856261B2 (en) * | 1998-03-18 | 2006-12-13 | ソニー株式会社 | Synchronous detection device |
| US6504867B1 (en) * | 1998-03-26 | 2003-01-07 | Analog Devices, Inc. | Digital matched filtering for signal estimation in a digital receiver |
| US6614834B1 (en) * | 1998-09-08 | 2003-09-02 | The Board Of Trustees Of The Leland Stanford Junior University | Communication arrangement and method with fast tracking receiver for spread spectrum signals |
| FI114887B (en) * | 1999-10-13 | 2005-01-14 | U Nav Microelectronics Corp | Signal detection system of a spread spectrum receiver |
-
2000
- 2000-09-29 FI FI20002154A patent/FI114887B/en not_active IP Right Cessation
- 2000-10-12 AU AU79252/00A patent/AU770577B2/en not_active Expired
- 2000-10-12 CA CA2385111A patent/CA2385111C/en not_active Expired - Lifetime
- 2000-10-12 DE DE60036010T patent/DE60036010T2/en not_active Expired - Lifetime
- 2000-10-12 WO PCT/FI2000/000879 patent/WO2001028116A1/en active Search and Examination
- 2000-10-12 EP EP00969580A patent/EP1222748B1/en not_active Expired - Lifetime
- 2000-10-12 AT AT00969580T patent/ATE370555T1/en not_active IP Right Cessation
- 2000-10-12 JP JP2001530222A patent/JP5059268B2/en not_active Expired - Lifetime
- 2000-10-13 US US09/689,750 patent/US6909739B1/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| US6909739B1 (en) | 2005-06-21 |
| JP2003511955A (en) | 2003-03-25 |
| EP1222748B1 (en) | 2007-08-15 |
| AU7925200A (en) | 2001-04-23 |
| FI20002154A (en) | 2001-04-14 |
| WO2001028116A1 (en) | 2001-04-19 |
| ATE370555T1 (en) | 2007-09-15 |
| FI20002154A0 (en) | 2000-09-29 |
| EP1222748A1 (en) | 2002-07-17 |
| JP5059268B2 (en) | 2012-10-24 |
| AU770577B2 (en) | 2004-02-26 |
| DE60036010T2 (en) | 2008-05-15 |
| CA2385111C (en) | 2010-02-16 |
| FI114887B (en) | 2005-01-14 |
| DE60036010D1 (en) | 2007-09-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2385111A1 (en) | Signal acquisition system for spread spectrum receiver | |
| CA2975448C (en) | Radio receiver for determining location of a signal source | |
| KR100295513B1 (en) | Spectrum direct spread signal receiver and acquisition circuit | |
| US6498585B2 (en) | Method and apparatus for rapidly estimating the doppler-error and other receiver frequency errors of global positioning system satellite signals weakened by obstructions in the signal path | |
| JP3819596B2 (en) | Pseudorandom noise detector for signals with carrier frequency offset | |
| GB2399261A (en) | Apparatus and method for a digital,wideband,intercept and analysis processor for frequency hopping signals | |
| CN102608626A (en) | High-sensitivity satellite navigation signal capturing method and system | |
| WO2003105495A3 (en) | System and method for improving the accuracy of time of arrival measurements in a wireless ad-hoc communications network | |
| US5199050A (en) | Pseudorandom (PN) signal synchronization circuit and related method | |
| CN109270831B (en) | BPM short wave multi-frequency point timing system | |
| WO1996029791A3 (en) | Method and apparatus for offset frequency estimation for a coherent receiver | |
| JPH09135234A (en) | Short burst trapping circuit for direct sequence spread spectrum link | |
| EP0809377A3 (en) | Signal acquisition in a satellite telephone system | |
| CN114563803A (en) | High-dynamic high-sensitivity Beidou D1 signal capturing method | |
| CN110601718A (en) | Spread spectrum communication capturing method, device and system | |
| CN107621643B (en) | Method for accurately resolving relevant domain parameters suitable for navigation signal quality evaluation | |
| EP1654555B1 (en) | A method of processing a sampled spread spectrum signal stream | |
| Johnson et al. | Broadband correlation processing | |
| RU2449298C1 (en) | Method for determination of noise energy | |
| KR19990065801A (en) | Rapid acquisition means and method of PN signal | |
| WO2002089349A8 (en) | Method and apparatus for code synchronisation in cdma | |
| CN115932716A (en) | Direction finding method and direction finding device matched with signal | |
| KR20020050242A (en) | Signal acquisition system for spread spectrum receiver |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKEX | Expiry |
Effective date: 20201013 |