Adaptive antenna reception apparatus with weight updated adaptively

• US 7,106,785 B2
• Filed: 06/05/2002
• Issued: 09/12/2006
• Est. Priority Date: 06/06/2001
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Yoshida, Shousei
• Primary Examiner(s): Ghebretinsae, Temesghen
• Application Number:
  US10/161,689
• Publication Number:
  US 20020187814A1
• Time in Patent Office: 1,560 Days
• Field of Search: 375/148, 375/144, 370/342, 370/479, 370/355, 370/339, 455/561, 455/25, 455/68, 455/517, 455/562.1, 455/422.1, 343/844, 343/853, 342/375, 342/373, 342/372, 342/383, 342/377, 342/378
• US Class Current: 375/148
• CPC Class Codes: H04B 7/0851 using training sequences or error signal minimizing error signal H04B7/0854

Abstract

An adaptive antenna reception apparatus includes a multi-beam former (1) provided in common to users, to convert antenna-corresponding spread signals received by antennas of an array antenna into beam-corresponding spread signals. A receiving and demodulating section (2) is provided for one of the users, generates beam-corresponding correlation signals at a path timing from the beam-corresponding spread signals, and generates path signals by weighting the beam-corresponding correlation signals with adaptive weights which are updated adaptively, and produces a demodulation signal for the one user by combining the path signals.

Claims

1. An adaptive antenna reception apparatus comprising:

a multi-beam former provided in common to a plurality of users, to convert antenna-corresponding spread signals received by antennas of an array antenna into beam-corresponding spread signals; and

a receiving and demodulating section, which is provided for a user in said plurality of users, generates beam-corresponding correlation signals at path timings from said beam-corresponding spread signals, and generates path signals by weighting said beam-corresponding correlation signals with adaptive weights which are updated adaptively, and produces a demodulation signal for said user by combining said path signals.

2. The adaptive antenna reception apparatus according to claim 1, wherein said multi-beam former comprises:

groups of former multipliers respectively provided for beam patterns of said array antenna, wherein each of said former multipliers of each of said groups multiplies one of said antenna-corresponding spread signals and a predetermined beam weight to produce said beam-weighted spread signal; and

former combining circuits, wherein each of said former combining units is provided for said group to combine said beam-weighted spread signals of said group to produce one of said beam-corresponding spread signals.

3. The adaptive antenna reception apparatus according to claim 1, wherein said receiving and demodulating section comprises:

receiving sections, each of which is provided for one of paths, generates said beam-corresponding correlation signals at said path timing from said beam-corresponding spread signals, generates one of said path signals for said path by weighting said beam-corresponding correlation signals with said adaptive weights, and updates said adaptive weights based on said beam-corresponding correlation signals and an error signal;

a reception combining unit provided for receiving sections, to combine said path signals from said receiving sections to output said demodulation signal; and

an error signal generating section which generates said error signal from said demodulation signal or a known reference signal to represent a difference between said demodulation signal and a transmission estimation signal from said one user or said known reference signal and distributes said error signal to said receiving sections.

4. The adaptive antenna reception apparatus according to claim 3, wherein said error signal generating section comprises:

a decision section which determines said transmission estimation signal from said demodulation signal;

a switch which selects as a reference signal, one of said known reference signal and said transmission estimation signal;

a subtractor which subtracts said demodulation signal from said reference signal to generate said error signal and distributes said error signal to said receiving sections.

5. The adaptive antenna reception apparatus according to claim 3, wherein said receiving section comprises:

a correlation unit which calculates correlations of said beam-corresponding spread signals at said path timing to produce beam-corresponding correlation signals;

a weighting and combining section which weights said beam-corresponding correlation signals outputted from said correlation unit with said adaptive weights and combines weighted beam-corresponding correlation signals to produce a weighted path signal;

a rake combining and weighting section which carries out a weighting operation to the weighted path signal to correct a phase change to generate said path signal and estimates a channel estimation signal from the weighted path signal;

a reception multiplier which multiplies said error signal and said channel estimation signal; and

a weight adaptive control section which updates said adaptive weights based on said beam-corresponding correlation signals and an output of said reception multiplier.

6. The adaptive antenna reception apparatus according to claim 5, wherein said receiving section further comprises:

a normalizing section which is provided between said rake combining and weighting section and said reception multiplier to carry out a normalizing operation to said channel estimation signal estimated by said rake combining and weighting section, and

wherein said reception multiplier which multiplies said error signal and an output of said normalizing section in place of said channel estimation signal.

7. The adaptive antenna reception apparatus according to claim 5, wherein said weighting and combining section comprises:

weighting complex conjugate calculating circuits which calculate complex conjugates of said adaptive weights;

weighting multipliers which multiply said beam-corresponding correlation signals and the complex conjugates of said adaptive weights; and

a weighting and combining circuit which combines outputs of said weighting multipliers into said weighted path signal.

8. The adaptive antenna reception apparatus according to claim 5, wherein said rake combining and weighting section comprises:

a channel estimating section which estimates said channel estimation signal from said weighted path signal;

a rake complex conjugate calculating circuit which calculates a complex conjugate of said channel estimation signal; and

a rake multiplier which multiplies said weighted path signal and said complex conjugate of said channel estimation signal to produce said path signal.

9. The adaptive antenna reception apparatus according to claim 5, wherein said rake combining and weighting section comprises:

a channel estimating section which estimates said channel estimation signal from said weighted path signal;

a rake complex conjugate calculating circuit which calculates a complex conjugate of said channel estimation signal;

a first rake multiplier which multiplies said weighted path signal and said complex conjugate of said channel estimation signal to produce said path signal;

an interference power estimating section which calculates interference power from said weighted path signal;

an inverse value calculating section which calculates an inverse number of said interference power; and

a second rake multiplier which multiplies an output of said first rake multiplier and an output of said inverse value calculating section.

10. The adaptive antenna reception apparatus according to claim 5, further comprises:

a path detecting section which detects said path timings from said beam-corresponding spread signals and outputs said path timing to said receiving sections.

11. The adaptive antenna reception apparatus according to claim 10, wherein said path detecting section comprises:

a sliding correlation unit which carries out a despreading operation to said beam-corresponding spread signals over a plurality of chips and outputs sequences of beam-corresponding despread signals;

a delay profile generating section which generates beam-corresponding delay profiles from said sequences of beam-corresponding despread signals;

a delay profile combining section which produces one delay profile by selecting and combining one or more of said beam-corresponding delay profiles; and

a path timing detecting section which detects said path timings from said delay profile and outputs said receiving and demodulating section.

12. The adaptive antenna reception apparatus according to claim 3, wherein said weight adaptive control section sets initial data of said adaptive weights in response to a beam selection signal, and

the adaptive antenna reception apparatus further comprises:

a path detecting section which detects said path timings from said beam-corresponding spread signals to outputs to said receiving sections, generates a delay profile and generates said beam selection signals from said delay profile and said path timings to output to said receiving sections.

13. The adaptive antenna reception apparatus according to claim 3, wherein said receiving section comprises:

an orthogonal multi-beam group selecting section which selects orthogonal ones from said beam-corresponding spread signals in response to a beam selection signal, said orthogonal beam-corresponding spread signals containing said beam-corresponding signal with a maximum level among said beam-corresponding spread;

a correlation unit which calculates correlations of said orthogonal beam-corresponding spread signals at said path timing to produce beam-corresponding correlation signals;

a weighting and combining section which weights said beam-corresponding correlation signals outputted from said correlation unit with said adaptive weights and combines weighted beam-corresponding correlation signals to produce a weighted path signal;

a rake combining and weighting section which carries out a weighting operation to the weighted path signal to correct a phase change to generate said path signal and estimates a channel estimation signal from the weighted path signal;

a reception multiplier which multiplies said error signal and said channel estimation signal; and

a weight adaptive control section which sets initial data of said adaptive weights in response to said beam selection signal, and updates said adaptive weights based on said beam-corresponding correlation signals and an output of said reception multiplier.

14. The adaptive antenna reception apparatus according to claim 13, further comprises:

a path detecting section which detects said path timings from said beam-corresponding spread signals to outputs to said receiving sections, generates a delay profile and generates said beam selection signals from said delay profile and said path timings to output to said receiving sections.

15. The adaptive antenna reception apparatus according to claim 14, wherein said path detecting section comprises:

a sliding correlation unit which carries out a despreading operation to said beam-corresponding spread signals over a plurality of chips and outputs sequences of beam-corresponding despread signals;

a delay profile generating section which generates beam-corresponding delay profiles from said sequences of beam-corresponding despread signals;

a delay profile combining section which produces a delay profile by selecting and combining one or more of said beam-corresponding delay profiles, and outputs levels of said delay profile;

a path timing detecting section which detects said path timings from said delay profile and outputs said receiving and demodulating section; and

a beam selection signal generating section which generates said beam selection signals from the levels of said delay profile in response to said path timings from said path timing detecting section.

18. The adaptive antenna reception apparatus according to claim 1, wherein said receiving and demodulating section comprises:

a correlation unit which calculates correlations of said beam-corresponding spread signals at said path timings to produce beam-corresponding correlation signals.

19. The adaptive antenna reception apparatus according to claim 18, wherein said receiving and demodulating section further comprises:

a weighting and combing section which weights said beam-corresponding correlation signals outputted from said correlation unit with said adaptive weights and combines weighted beam-corresponding correlation signals to produce a weighted path signal.

20. The adaptive antenna reception apparatus according to claim 19, wherein said receiving and demodulating section further comprises:

an error signal generating section which generates an error signal from one of said demodulation signal and a known reference signal;

a rake combining and weighting section which carries out a weight operation to the weighted path signal to correct a phase change to generate said path signal and estimates a channel estimation signal from the weighted path signal;

a reception multiplier which multiplies said error signal and said channel estimation signal; and

a weight adaptive control section which updates said adaptive weights based on said beam-corresponding correlation signals and an output of said reception multiplier.

16. An adaptive antenna reception apparatus comprising:

a multi-beam former provided in common to a plurality of users, to convert antenna-corresponding spread signals received by antennas of an array antenna into beam-corresponding spread signals;

a receiving and demodulating section which is provided for a user in said plurality of users, and which generates beam-corresponding correlation signals at path timings from said beam-corresponding spread signals, and generates path signals by weighting said beam-corresponding correlation signals with adaptive weights which are updated adaptively, and produces a demodulation signal for said user by combining said path signals; and

a path detecting section which detects said path timings from said beam-corresponding spread signals and outputs said path timings to said receiving and demodulating section.

17. An adaptive antenna reception apparatus comprising:

a multi-beam former provided in common to a plurality of users, to convert antenna-corresponding spread signals received by antennas of an array antenna into beam-corresponding spread signals;

receiving and demodulating sections which are provided for said plurality users, and each of which generates beam-corresponding correlation signals at a path timing from said beam-corresponding spread signals, and generates path signals by weighting said beam-corresponding correlation signals with adaptive weights which are updated adaptively, and produces a demodulation signal for a user in said plurality users by combining said path signals, initial data of said adaptive weights being set in response to said beam selection signal; and

a path detecting section which detects said path timings from said beam-corresponding spread signals to outputs to said receiving and demodulating section, generates a delay profile and generates said beam selection signals from said delay profile and said path timings to output to said receiving sections.