Radio receiving system and synchronization detection method

• US 7,076,212 B1
• Filed: 10/25/2000
• Issued: 07/11/2006
• Est. Priority Date: 11/08/1999
• Status: Expired due to Term

• Current Assignee: Hera Wireless S.A. (Fineur International S.A.)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Doi, Yoshiharu, Miyata, Takeo
• Primary Examiner(s): Milord, Marceau
• Application Number:
  US10/111,414
• Time in Patent Office: 2,085 Days
• Field of Search: 455/63.1, 455/526, 455/501, 455/67.13, 455/570, 455/562.1, 455/575.7, 455/101, 455/135, 375/150, 375/149, 375/142, 375/342, 375/130, 375/148, 375/354, 375/367, 370/342, 370/350, 370/335
• US Class Current: 455/63.1
• CPC Class Codes: H04B 7/08 at the receiving station
• CPC Class Codes: H04B 7/0851 using training sequences or error signal minimizing error signal H04B7/0854
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 7/042 Detectors therefor, e.g. correlators, state machines digital correlators in general G06F17/15

Abstract

A weight vector of a precedent frame calculated by a weight vector calculator (4) and stored in a memory (3) is applied to a signal received through a plurality of antennas (ANT₁, . . . ANT_n) for removing an interference wave component. A synchronous position is detected from the signal subjected to removal of the interference wave component by a method of correlation synchronization, and supplied to the weight vector calculator (4). The weight vector calculator (4) executes calculation of a weight vector with the detected synchronous position as a start position. Thus, when signals of the same frequency are received in a CS in an overlapping manner, the synchronous position of a signal received from a desired PS can be correctly specified.

Claims

1. A radio receiving system (1) receiving a signal from a mobile terminal unit with a plurality of antennas (ANT₁, . . . , ANT_n), comprising:

first interference removal means (MPA₁, . . . , MPA_n, ADDA,

     4) provisionally removing an interference signal component from received said signal;

correlation synchronization detection means (5, 6) detecting correlation synchronization of said received signal subjected to removal of the interference signal component by said first interference removal means; and

second interference removal means (MPB₁, . . . , MPB_n, ADDB,

     4) removing an interference signal component from said received signal with a synchronous position detected by said correlation synchronization detection means as a start position.

2. A radio receiving system (1) receiving a signal from a mobile terminal unit with a plurality of antennas (ANT₁, . . . , ANT_n), comprising:

weight vector calculation means (4) calculating a weight vector corresponding to a desired mobile terminal unit every frame of received said signal;

storage means (3) storing said calculated weight vector;

first signal extraction means (MPA₁, . . . , MPA_n, ADDA) applying said weight vector of a precedent frame stored in said storage means to a frame of newly received said signal and extracting a signal from said desired mobile terminal unit;

correlation function calculation means (5) calculating a correlation function of said extracted signal and a prescribed reference signal;

synchronous position detection means (6) detecting a time position where said correlation function peaks as a synchronous position; and

second signal extraction means (MPB₁, . . . , MPB_n, ADDB) applying the weight vector of the frame of said newly received signal calculated by said weight vector calculation means to the frame of said newly received signal for extracting and outputting the signal from said desired mobile terminal unit, wherein

said weight vector calculation means calculates the weight vector of the frame of said newly received signal with said detected synchronous position as a start position.

3. A radio receiving system (1) receiving a signal from a mobile terminal unit with a plurality of antennas (ANT₁, . . . , ANT_n), comprising:

weight vector calculation means (4) calculating a weight vector corresponding to a desired mobile terminal unit every frame of received said signal;

first storage means (3) storing said calculated weight vector;

mode set means (9) setting a synchronization capture mode or a synchronization protection mode;

first signal extraction means (MPA₁, . . . , MPA_n, ADDA) applying said weight vector of a precedent frame stored in said first storage means to a frame of newly received said signal and extracting a signal from said desired mobile terminal unit in said synchronization capture mode;

correlation function calculation means (5) calculating a correlation function of the signal extracted by said first signal extraction means and a prescribed reference signal in said synchronization capture mode;

synchronous position detection means (6) detecting a time position where said correlation function peaks as a synchronous position in said synchronization capture mode;

second storage means (3) storing said detected synchronous position;

second signal extraction means (MPB₁, . . . , MPB_n, ADDB) applying the weight vector of the frame of said newly received signal calculated by said weight vector calculation means to the frame of said newly received signal for extracting and outputting the signal from said desired mobile terminal unit; and

error determination means (8) determining whether or not the signal extracted by said second signal extraction means has a receiving error, wherein

said weight vector calculation means calculates the weight vector of the frame of said newly received signal with the synchronous position detected by said synchronous position detection means as a start position in said synchronization capture mode or with the synchronous position stored in said second storage means as a start position in said synchronization protection mode, and

said mode set means sets said synchronization protection mode when said error determination means determines that there is no error in said synchronization capture mode while maintaining said synchronization capture mode when said error determination means determines that there is an error in said synchronization capture mode and sets said synchronization capture mode when said error determination means continuously determines that there is an error in excess of a prescribed number of times in said synchronization protection mode while maintaining said synchronization protection mode when said prescribed number of times is not reached in said synchronization protection mode.

4. A radio receiving system (1) receiving a signal from a mobile terminal unit with a plurality of antennas (ANT₁, . . . ANT_n), comprising:

weight vector calculation means (4) calculating a weight vector corresponding to a desired mobile terminal unit every frame of received said signal;

first storage means (3) storing said calculated weight vector;

mode set means (9) setting a synchronization capture mode or a synchronization protection mode;

first signal extraction means (MPA₁, . . . , MPA_n, ADDA) applying said weight vector of a precedent frame stored in said first storage means in said synchronization capture mode or the weight vector of the frame of newly received said signal calculated by said weight vector calculation means in said synchronization protection mode to the frame of said newly received signal and extracting a signal from said desired mobile terminal unit;

correlation function calculation means (5) calculating a correlation function of the signal extracted by said first signal extraction means and a prescribed reference signal;

synchronous position detection means (6) detecting a time position where said correlation function peaks as a synchronous position;

second storage means (3) storing said detected synchronous position;

second signal extraction means (MPB₁, . . . , MPB_n, ADDB) applying the weight vector of the frame of said newly received signal calculated by said weight vector calculation means to the frame of said newly received signal for extracting and outputting the signal from said desired mobile terminal unit; and

error determination means (8) determining whether or not the signal extracted by said second signal extraction means has a receiving error, wherein

said weight vector calculation means calculates the weight vector of the frame of said newly received signal with the synchronous position detected by said synchronous position detection means as a start position in said synchronization capture mode or with the synchronous position stored in said second storage means as a start position in said synchronization protection mode, and

said mode set means sets said synchronization protection mode when said error determination means determines that there is no error in said synchronization capture mode while maintaining said synchronization capture mode when said error determination means determines that there is an error in said synchronization capture mode and sets said synchronization capture mode when said error determination means continuously determines that there is an error in excess of a prescribed number of times in said synchronization protection mode while maintaining said synchronization protection mode when said prescribed number of times is not reached in said synchronization protection mode,

said radio receiving system further comprising means (12) comparing the synchronous position detected by said synchronous position detection means with the synchronous position stored in said second storage means in said synchronization protection mode for updating the synchronous position stored in said second storage means when the difference between the synchronous positions exceeds a prescribed magnitude.

5. A synchronization detection method in a radio receiving system (1) receiving a signal from a mobile terminal unit with a plurality of antennas (ANT₁, . . . , ANT_n), comprising steps of:

provisionally an interference signal component from received said signal;

detecting correlation synchronization of said received signal subjected to removal of the interference signal component; and

removing an interference signal component from said received signal with the synchronous position detected by said correlation synchronization detection as a start position.

6. A synchronization detection method in a radio receiving system (1) receiving a signal from a mobile terminal unit with a plurality of antennas (ANT₁, . . . , ANT_n), comprising steps of:

calculating a weight vector corresponding to a desired mobile terminal unit every frame of received said signal;

storing said calculated weight vector;

applying said stored weight vector of a precedent frame to a frame of newly received said signal and extracting a signal from said desired mobile terminal unit;

calculating a correlation function of said extracted signal and a prescribed reference signal;

detecting a time position where said correlation function peaks as a synchronous position; and

applying the calculated weight vector of the frame of said newly received signal to the frame of said newly received signal for extracting and outputting the signal from said desired mobile terminal unit, wherein

said step of calculating said weight vector performs calculation of the weight vector of the frame of said newly received signal with said detected synchronous position as a start position.

7. A synchronization detection method in a radio receiving system (1) receiving a signal from a mobile terminal unit with a plurality of antennas (ANT₁, . . . , ANT_n), comprising steps of:

calculating a weight vector corresponding to a desired mobile terminal unit every frame of received said signal;

storing said calculated weight vector;

setting a synchronization capture mode or a synchronization protection mode;

applying said stored weight vector of a precedent frame to a frame of newly received said signal and extracting a signal from said desired mobile terminal unit in said synchronization capture mode;

calculating a correlation function of said extracted signal and a prescribed reference signal in said synchronization capture mode;

detecting a time position where said correlation function peaks as a synchronous position in said synchronization capture mode;

storing said detected synchronous position;

applying the calculated weight vector of the frame of said newly received signal to the frame of said newly received signal for extracting and outputting the signal from said desired mobile terminal unit; and

determining whether or not said extracted signal has a receiving error, wherein

said step of calculating said weight vector performs calculation of the weight vector of the frame of said newly received signal with said detected synchronous position as a start position in said synchronization capture mode or with said stored synchronous position as a start position in said synchronization protection mode, and

said step of setting said mode sets said synchronization protection mode when it is determined that there is no error in said synchronization capture mode while maintaining said synchronization capture mode when it is determined that there is an error in said capture mode and sets said synchronization capture mode when it is continuously determined that there is an error in excess of a prescribed number of times in said synchronization protection mode while maintaining said synchronization protection mode when said prescribed number of times is not reached in said synchronization protection mode.

8. A synchronization detection method in a radio receiving system (1) receiving a signal from a mobile terminal unit with a plurality of antennas (ANT₁, . . . ANT_n), comprising steps of:

calculating a weight vector corresponding to a desired mobile terminal unit every frame of received said signal;

storing said calculated weight vector;

setting a synchronization capture mode or a synchronization protection mode;

applying said stored weight vector of a precedent frame in said synchronization capture mode or said calculated weight vector of the frame of newly received said signal in said synchronization protection mode to the frame of said newly said signal and extracting a signal from said desired mobile terminal unit;

calculating a correlation function of said extracted signal and a prescribed reference signal;

detecting a time position where said correlation function peaks as a synchronous position;

storing said detected synchronous position;

applying the calculated weight vector of the frame of said newly received signal to the frame of said newly received signal for extracting and outputting the signal from said desired mobile terminal unit; and

determining whether or not said extracted signal has a receiving error, wherein

said step of calculating said weight vector performs calculation of the weight vector of the frame of said newly received signal with said detected synchronous position as a start position in said synchronization capture mode or with said stored synchronous position as a start position in said synchronization protection mode, and

said step of setting said mode sets said synchronization protection mode when it is determined that there is no error in said synchronization capture mode while maintaining said synchronization capture mode when it is determined that there is an error in said synchronization capture mode and sets said synchronization capture mode when it is continuously determined that there is an error in excess of a prescribed number of times in said synchronization protection mode while maintaining said synchronization protection mode when said prescribed number of times is not reached in said synchronization protection mode,

said synchronization detection method further comprising a step of comparing said detected synchronous position with said stored synchronous position in said synchronization protection mode for updating said stored synchronous position when the difference between the synchronous positions exceeds a prescribed magnitude.