Diversity receiver

• US 5,757,866 A
• Filed: 11/10/1995
• Issued: 05/26/1998
• Est. Priority Date: 04/26/1995
• Status: Expired due to Term

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Oikawa, Hiroki, Kannari, Hideyuki, Shibata, Manabu
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): Roundtree, Joseph
• Application Number:
  US08/559,162
• Time in Patent Office: 928 Days
• Field of Search: 375/347, 375/231, 375/349, 455/135, 455/139, 455/137, 455/263, 455/273, 455/276.1, 455/304, 455/132, 327/105, 327/355, 327/360, 327/361, 327/354, 370/321
• US Class Current: 375/347
• CPC Class Codes: H04B 7/0842 Weighted combining
• CPC Class Codes: H04B 7/0865 Independent weighting, i.e. weights based on own antenna reception parameters

Abstract

A diversity receiver respectively receiving signals in two branches includes two demodulating sections for producing respective amplitude and phases of received signals at a unit of symbol. The receiver includes a memory access section for producing an amplitude ratio of the amplitude of the received signals and a phase difference between the phases of the received signals. The receiver further includes a storage section for storing at least one relative phase difference between a phase of a vector-combined signal combined based on the received signals and one of the phases of the received signals for an address given by the amplitude ratio and the phase difference of the received signals. The phase of the vector-combined signal is previously calculated based on the amplitude ratio, the phase difference, and the one of the phases of the received signals. The receiver further includes an adding section for adding the relative phase difference produced from the storage section being addressed by the amplitude ratio and the phase difference produced from the memory access section to the one of the phases of the received signals to produce the phase of the vector-combined signal combined based on the received signals.

Claims

1. A diversity receiver respectively receiving signals in at least two branches, the diversity receiver comprising:

at least two demodulating means respectively provided for said at least two branches for producing respective amplitude and phases of received signals at a unit of symbol;

memory access means for producing an amplitude ratio of said amplitude of the received signals and a phase difference between the phases of the received signals;

storage means for storing at least one relative phase difference between a phase of a vector-combined signal combined based on the received signals and one of the phases of the received signals for an address given by said amplitude ratio and said phase difference of the received signals, said phase of the vector-combined signal being previously calculated based on said amplitude ratio, said phase difference, and said one of the phases of the received signals; and

adding means for adding said relative phase difference produced from said storage means being addressed by said amplitude ratio and said phase difference produced from the memory access means to said one of the phases of the received signals to produce said phase of the vector-combined signal combined based on the received signals.

7. The diversity receiver as claimed in claim 1, wherein said vector-combined signal is a signal generated by combining the received signals with squaring the respective amplitude of the received signals.

2. A diversity receiver respectively receiving signals in at least two branches, said diversity receiver comprising:

at least two demodulating means respectively provided for said at least two branches for producing respective amplitude and phases of received signals at a unit of symbol;

memory access means for producing an amplitude ratio of said amplitude of the received signals and a phase difference between the phases of the received signals; and

storage means for storing at least one phase of a vector-combined signal combined based on the received signals for an address given by said amplitude ratio and said phase difference and one of the phases of the received signals, said phase of the vector-combined signal being previously calculated based on said amplitude ratio, said phase difference, and said one of the phases of the received signals;

wherein said phase of the vector-combined signal is produced from said storage means by providing to the storage means said amplitude ratio and said phase difference from the memory access means and said one of the phases of the received signals from said demodulating means at the symbol unit.

8. The diversity receiver as claimed in claim 2, wherein said vector-combined signal is a signal generated by combining the received signals with squaring the respective amplitude of the received signals.

3. A diversity receiver respectively receiving signals in at least two branches, said diversity receiver comprising:

at least two demodulating means respectively provided for said at least two branches for producing respective amplitude and phases of received signals at a unit of symbol;

memory access means for producing an amplitude ratio of said amplitude of the received signals and a phase difference between the phases of the received signals;

phase selecting means for selecting the phase of a larger amplitude one of said received signals;

storage means for storing at least one relative phase difference between a phase of a vector-combined signal combined based on the received signals and said phase of the larger amplitude one of the received signals for an address given by said amplitude ratio and said phase difference of said received signals, said phase of the vector-combined signal being previously calculated based on said amplitude ratio and said phase difference of the received signals and said phase of the larger amplitude one of the received signals; and

adding means for adding said relative phase difference produced from said storage means being accessed by the amplitude ratio and the phase difference produced from the memory access means to said phase selected in the phase selecting means to produce said phase of the vector-combined signal combined based on the received signals.

9. The diversity receiver as claimed in claim 3, wherein said vector-combined signal is a signal generated by combining the received signals with squaring the respective amplitude of the received signals.

4. A diversity receiver respectively receiving signals in at least two branches, the diversity receiver comprising:

at least two demodulating means respectively provided for said at least two branches for producing respective amplitude and phases of received signals at a unit of symbol;

memory access means for producing an amplitude ratio of said amplitude of the received signals and a phase difference between the phases of the received signals;

phase selecting means for selecting a smaller one of said phases of the received signals;

storage means for storing at least one relative phase difference between a phase of a vector-combined signal combined based on the received signals and said smaller one of the phases of the received signals for an address given by said amplitude ratio and said phase difference of the received signals, said phase of the vector-combined signal being previously calculated based on said amplitude ratio and said phase difference of the received signals and said smaller one of the phases of the received signals; and

adding means for adding said relative phase difference produced from said storage means being accessed by the amplitude ratio and the phase difference produced from the memory access means to said smaller one of the phases of the received signals selected in the phase selecting means to produce said phase of the vector-combined signal combined based on the received signals.

10. The diversity receiver as claimed in claim 4, wherein said vector-combined signal is a signal generated by combining the received signals with squaring the respective amplitude of the received signals.

5. A diversity receiver respectively receiving signals in at least two branches, the diversity receiver comprising:

at least two demodulating means respectively provided for said at least two branches for producing respective amplitude and phases of received signals at a unit of symbol;

memory access means for producing an amplitude ratio of said amplitude of the received signals and a phase difference between the phases of the received signals;

phase selecting means for selecting the phase of a larger amplitude one of said received signals; and

storage means for storing at least one phase of a vector-combined signal combined based on the received signals for an address given by said amplitude ratio and said phase difference of the received signals and said phase of the larger amplitude one of the received signals, said phase of the vector-combined signal being previously calculated based on said amplitude ratio and said phase difference of the received signals and said phase of the larger amplitude one of the received signals;

wherein said phase of the vector-combined signal is produced from said storage means by providing to the storage means said amplitude ratio and said phase difference from the memory access means and said phase selected in the phase selecting means at the symbol unit.

11. The diversity receiver as claimed in claim 5, wherein said vector-combined signal is a signal generated by combining the received signals with squaring the respective amplitude of the received signals.

6. A diversity receiver respectively receiving signals in at least two branches, the diversity receiver comprising:

at least two demodulating means respectively provided for said at least two branches for producing respective amplitude and phases of received signals at a unit of symbol;

memory access means for producing an amplitude ratio of said amplitude of the received signals and a phase difference between the phases of the received signals;

phase selecting means for selecting a smaller one of said phases of the received signals; and

storage means for storing at least one phase of a vector-combined signal combined based on the received signals for an address given by said amplitude ratio and said phase difference of the received signals and said smaller one of the phases of the received signals, said phase of the vector-combined signal being previously calculated based on said amplitude ratio and said phase difference of the received signals and said smaller one of the phases of the received signals;

wherein said phase of the vector-combined signal is produced from said storage means by providing to the storage means said amplitude ratio and said phase difference from the memory access means and said smaller one of the phases of the received signals selected in the phase selecting means at the symbol unit.

12. The diversity receiver as claimed in claim 6, wherein said vector-combined signal is a signal generated by combining the received signals with squaring the respective amplitude of the received signals.