AU2002221628A1 - Adaptive filtering and dc offset removal for communications systems - Google Patents

Adaptive filtering and dc offset removal for communications systems

Info

Publication number
AU2002221628A1
AU2002221628A1 AU2002221628A AU2162802A AU2002221628A1 AU 2002221628 A1 AU2002221628 A1 AU 2002221628A1 AU 2002221628 A AU2002221628 A AU 2002221628A AU 2162802 A AU2162802 A AU 2162802A AU 2002221628 A1 AU2002221628 A1 AU 2002221628A1
Authority
AU
Australia
Prior art keywords
channel
filter
power
adjacent channel
communications systems
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.)
Abandoned
Application number
AU2002221628A
Inventor
Peter Jakobsson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Telefonaktiebolaget LM Ericsson AB
Original Assignee
Telefonaktiebolaget LM Ericsson AB
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Telefonaktiebolaget LM Ericsson AB filed Critical Telefonaktiebolaget LM Ericsson AB
Publication of AU2002221628A1 publication Critical patent/AU2002221628A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
    • H04L27/22—Demodulator circuits; Receiver circuits
    • H04L27/233—Demodulator circuits; Receiver circuits using non-coherent demodulation
    • H04L27/2338—Demodulator circuits; Receiver circuits using non-coherent demodulation using sampling
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03D—DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER
    • H03D3/00—Demodulation of angle-, frequency- or phase- modulated oscillations
    • H03D3/007—Demodulation of angle-, frequency- or phase- modulated oscillations by converting the oscillations into two quadrature related signals
    • H03D3/008—Compensating DC offsets
    • 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
    • H04B1/06—Receivers
    • H04B1/16—Circuits
    • H04B1/30—Circuits for homodyne or synchrodyne receivers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/06—Dc level restoring means; Bias distortion correction ; Decision circuits providing symbol by symbol detection
    • H04L25/061—Dc level restoring means; Bias distortion correction ; Decision circuits providing symbol by symbol detection providing hard decisions only; arrangements for tracking or suppressing unwanted low frequency components, e.g. removal of dc offset
    • H04L25/062—Setting decision thresholds using feedforward techniques only

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Power Engineering (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Dc Digital Transmission (AREA)
  • Circuits Of Receivers In General (AREA)
  • Noise Elimination (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Networks Using Active Elements (AREA)

Abstract

Adaptive channel filtration enables a filter to be adaptively optimized for both co-channel and adjacent channel rejection performance (e.g., even as conditions change in a Rayleigh-fading environment). Principles of the present invention may be incorporated into a homodyne-based receiver architecture. In an exemplary homodyne-based receiver, the power of the adjacent channel interferer is calculated (e.g., determined, estimated, etc.), and an associated (e.g., low pass) channel filter is adapted depending on a ratio involving the total power (e.g., the desired channel plus the adjacent channel) and the adjacent channel power. In one or more embodiments, such a ratio is used with a look up table to produce a desired channel filter bandwidth, which may be used as a basis for creating coefficients for utilization by a low pass channel filter.
AU2002221628A 2000-10-02 2001-09-25 Adaptive filtering and dc offset removal for communications systems Abandoned AU2002221628A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US09/678,164 US6977978B1 (en) 2000-10-02 2000-10-02 Adaptive channel filtration for communications systems
US09678164 2000-10-02
PCT/EP2001/011084 WO2002030080A1 (en) 2000-10-02 2001-09-25 Adaptive filtering and dc offset removal for communications systems

Publications (1)

Publication Number Publication Date
AU2002221628A1 true AU2002221628A1 (en) 2002-04-15

Family

ID=24721660

Family Applications (1)

Application Number Title Priority Date Filing Date
AU2002221628A Abandoned AU2002221628A1 (en) 2000-10-02 2001-09-25 Adaptive filtering and dc offset removal for communications systems

Country Status (7)

Country Link
US (1) US6977978B1 (en)
EP (1) EP1323270B1 (en)
AT (1) ATE360315T1 (en)
AU (1) AU2002221628A1 (en)
DE (1) DE60127981D1 (en)
TW (1) TW548995B (en)
WO (1) WO2002030080A1 (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7230975B2 (en) * 2001-08-07 2007-06-12 Qualcomm Incorporated Adaptive pilot filter for a wireless communication system
US7277688B2 (en) * 2003-06-17 2007-10-02 Broadcom Corporation DC offset correction for very low intermediate frequency receiver
US7395064B2 (en) * 2004-07-14 2008-07-01 Intel Corporation Systems and methods of distributed self-configuration for wireless networks
GB0423708D0 (en) * 2004-10-26 2004-11-24 Koninkl Philips Electronics Nv Adapting filter to detected interference level
DE102007037105A1 (en) * 2007-05-09 2008-11-13 Rohde & Schwarz Gmbh & Co. Kg Method and device for detecting simultaneous double transmission of AM signals
US8537284B2 (en) * 2009-03-20 2013-09-17 Advanced Micro Devices, Inc. Adjacent channel power scan
US20150222459A1 (en) * 2014-02-04 2015-08-06 Qualcomm Incorporated Methods and devices for dynamic filter configuration in the presence of adjacent channel interference (aci)
WO2019120562A1 (en) 2017-12-22 2019-06-27 Telefonaktiebolaget Lm Ericsson (Publ) Altering filtering by changing mixing frequency when interferer present
CN114451333B (en) * 2022-02-11 2023-03-14 南宁市水产畜牧兽医技术推广站 Eel intensive culture method

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5561424A (en) * 1993-04-30 1996-10-01 Lucent Technologies Inc. Data converter with minimum phase fir filter and method for calculating filter coefficients
US5640416A (en) * 1995-06-07 1997-06-17 Comsat Corporation Digital downconverter/despreader for direct sequence spread spectrum communications system
JP2882364B2 (en) * 1996-06-14 1999-04-12 日本電気株式会社 Noise cancellation method and noise cancellation device
GB2328353B (en) 1997-08-16 2002-10-02 Nec Technologies GSM mobile receiver
US6047171A (en) 1998-01-08 2000-04-04 Ericsson Inc. Method and apparatus for combating adjacent channel interference using multiple IF filters
WO2000072441A1 (en) * 1999-05-24 2000-11-30 Level One Communications, Inc. Automatic gain control and offset correction
US6370205B1 (en) * 1999-07-02 2002-04-09 Telefonaktiebolaget Lm Ericsson (Publ) Method and apparatus for performing DC-offset compensation in a radio receiver

Also Published As

Publication number Publication date
ATE360315T1 (en) 2007-05-15
TW548995B (en) 2003-08-21
DE60127981D1 (en) 2007-05-31
WO2002030080A1 (en) 2002-04-11
US6977978B1 (en) 2005-12-20
EP1323270A1 (en) 2003-07-02
EP1323270B1 (en) 2007-04-18

Similar Documents

Publication Publication Date Title
EP1259016A3 (en) Sequential decoding with backtracking and adaptive equalization to combat narrowband interference
DE69920244T2 (en) Adaptive receiver for wireless communication
AU6647400A (en) Adaptive channel estimation in a wireless communication system
WO2007109296A3 (en) Downlink coordinated transmission in ofdma systems
WO2004036811A3 (en) Method and apparatus for interference suppression with efficient matrix inversion in a ds-cdma system
AU2002221628A1 (en) Adaptive filtering and dc offset removal for communications systems
GR3036993T3 (en) Radiotelephone filtering apparatus
WO2002080381A3 (en) Radio receiver having a dynamic bandwidth filter and method therefor
AU2002235217A1 (en) Multi-carrier communications with adaptive cluster configuration and switching
EP2239878A3 (en) Receiver adjustment between pilot bursts
WO2003050991A3 (en) System and method for improving data transmission
WO2005043796A3 (en) Method and system for an adaptive wireless communication system optimized for economic benefit
AU2008200260A1 (en) Apparatus, and associated method, for filtering a receive signal by adaptive operation of an input noise whitening filter
EP0729254A3 (en) Fractionally spaced equalizing circuits and method
WO2005062815A3 (en) Device with improved serial communication
AU2002307589A1 (en) Complexity reduction of linear interference canceling scheme
EP2048842A3 (en) Communications system using adaptive filter for interference reduction
EP1220351B8 (en) High performance microwave filter
Yang et al. Digital-carrier multi-band user codes for baseband UWB multiple access
AU2003278043A1 (en) Cascade filter receiver for ds-cdma communication systems
CA2220239A1 (en) Selective filtering for co-channel interference reduction
Chen et al. SNR and SIR estimation for multiuser UWB IR systems with TH-BPSK
TW200501596A (en) Communications for inductive power systems
WO2003051039A3 (en) Method of and system to set a quality of a media frame
Potman et al. Adaptive receive filter structures for UMTS