Diversity receiving apparatus

Claim 2

A diversity receiving apparatus for selecting and extracting a received signal of a good receiving state from a plurality of received signals, comprising: a plurality of receivers each of which is constructed by a detector for selecting a desired signal from said received signals and a demodulator for demodulating the selected signal; a level comparator for comparing each received signal level of the signal selected by each of said detectors of said plurality of receivers; a selector for selecting a demodulated signal from said demodulator of the receiver having the high received signal level on the basis of the comparison result in said level comparator and for outputting the selected demodulated signal; and a power controller for controlling a power supply to said plurality of receivers and said level comparator, wherein said power controller supplies electric powers to all of said receivers and said level comparator in accordance with a preset period of the comparison of the received signal levels and continues only the power supply to the receiver having the high received signal level on the basis of the comparison result in said level comparator and stops the power supply to the receivers other than said receiver having the high received signal level and to said level comparator.

Claim 3

An apparatus according to claim 1, wherein each of said receiver comprises a delay circuit which is provided at the post stage of said demodulator and delays the signal demodulated by said demodulator.

Claim 4

An apparatus according to claim 2, wherein said delay circuit has a delay time according to a time which is required for the comparison of the received signal levels in said level comparator.

Claim 5

An apparatus according to claim 1, wherein each of said receivers comprises a delay circuit which is provided between said detector and said demodulator and delays the signal selected by said detector.

Claim 6

An apparatus according to claim 4, wherein said delay circuit has a delay time according to a time which is required for the comparison of the received signal levels in said level comparator.

Claim 7

A diversity receiving apparatus which is used in a digital communication system using a time division multiple access system for selecting and extracting a received signal of a good receiving state from a plurality of received signals, comprising: a plurality of receivers each of which is constructed by a detector for selecting the signal of a desired slot from the received signals of said time division multiple access system and a demodulator for demodulating the signal of the selected slot; a level comparator for comparing each received signal level of the signal of the slot selected by each of said detectors of said plurality of receivers; a selector for selecting a demodulated signal from the demodulator of the receiver having the high received signal level on the basis of the comparison result in said level comparator and for outputting the selected demodulated signal; and a power controller for controlling a power supply to said plurality of receivers and said level comparator, wherein said power controller executes the power supply to all of said receivers and said level comparator in a head portion of the slot at which the reception is desired in accordance with a frame period of said time division multiple access system, continues only the power supply to the receiver having the high received signal level on the basis of the comparison result in said level comparator, and stops the power supply to the receivers other than the receiver having the high received signal level and to said level comparator.

Claim 8

A diversity receiving apparatus which is used in a digital communication system using a time division multiple access system for selecting and extracting a received signal of a good receiving state from a plurality of received signals, comprising: a plurality of receivers each of which is constructed by a detector for selecting the signal of a desired slot from the received signals of said time division multiple access system and a demodulator for demodulating the signal of the selected slot; a level comparator for comparing each received signal level of the signal of the slot selected by each of said detectors of said plurality of receivers; a selector for selecting a demodulated signal from the demodulator of the receiver having the high received signal level on the basis of the comparison result in said level comparator and for outputting the selected demodulated signal; and a power controller for controlling a power supply to said plurality of receivers and said level comparator, wherein said power controller executes the power supply to all of said receivers and said level comparator in a head portion of the slot at which the reception is desired in accordance with a frame period of said time division multiple access system, continues only the power supply to the receiver having the high received signal level on the basis of the comparison result in said level comparator, and stops the power supply to the receivers other than the receiver having the high received signal level and to said level comparator.

Claim 9

An apparatus according to claim 6, wherein each of said receivers further comprises a delay circuit which is provided at a post stage of said demodulator and delays the signal demodulated by said demodulator.

Claim 10

An apparatus according to claim 7, wherein said delay circuit has a delay time according to a time which is required for the comparison of the received signal levels in said level comparator.

Claim 11

An apparatus according to claim 6, wherein each of said receivers comprises a delay circuit which is provided between said detector and said demodulator and delays the signal of the slot selected by said detector.

Claim 12

An apparatus according to claim 9, wherein said delay circuit has a delay time according to a time which is required for the comparison of the received signal levels in said level comparator.

Claim 13

A diversity receiving apparatus for selecting and extracting a received signal of a good receiving state from a plurality of received signals, comprising: a plurality of receivers each of which is constructed by a detector for selecting a desired signal from said received signals and a demodulator for demodulating the selected signal; a level comparator for comparing each of the received signal levels of the signal selected by each of said detectors of said plurality of receivers; a selector for selecting a demodulated signal from said demodulator of the receiver having the high received signal level on the basis of the comparison result in said level comparator and for outputting the selected demodulated signal; a data processor for storing the detection result of the past received signal level, for analyzing an aging change of the detection result of the received signal level, and for deciding a period of the comparison of the received signal levels in accordance with an aging fluctuation amount of the received signal level; and a power controller for controlling a power supply to said plurality of receivers and said level comparator, wherein said power controller executes the power supply to all of said receivers and said level comparator in accordance with the period of the comparison of the received signal levels decided by said data processor, continues only the power supply to the receiver having the high received signal level on the basis of the comparison result in said level comparator, and stops the power supply to the receivers other than the receiver having the high received signal level and to said level comparator.

Claim 14

A diversity receiving apparatus for selecting and extracting a received signal of a good receiving state from a plurality of received signals, comprising: a plurality of receivers each of which is constructed by a detector for selecting a desired signal from said received signals and a demodulator for demodulating the selected signal; a level comparator for comparing each of the received signal levels of the signal selected by each of said detectors of said plurality of receivers; a selector for selecting a demodulated signal from said demodulator of the receiver having the high received signal level on the basis of the comparison result in said level comparator and for outputting the selected demodulated signal; a data processor for storing the detection result of the past received signal level, for analyzing an aging change of the detection result of the received signal level, and for deciding a period of the comparison of the received signal levels in accordance with an aging fluctuation amount of the received signal level; and a power controller for controlling a power supply to said plurality of receivers and said level comparator, wherein said power controller executes the power supply to all of said receivers and said level comparator in accordance with the period of the comparison of the received signal levels decided by said data processor, continues only the power supply to the receiver having the high received signal level on the basis of the comparison result in said level comparator, and stops the power supply to the receivers other than the receiver having the high received signal level and to said level comparator.

Claim 15

An apparatus according to claim 11, wherein each of said receivers comprises a delay circuit which is provided at the post stage of said demodulator and delays the signal demodulated by said demodulator.

Claim 16

An apparatus according to claim 12, wherein said delay circuit has a delay time according to a time which is required for the comparison of the received signal levels in said level comparator.

Claim 17

An apparatus according to claim 11, wherein each of said receivers comprises a delay circuit which is provided between said detector and said demodulator and delays the signal selected by said detector.

Claim 18

An apparatus according to claim 14, wherein said delay circuit has a delay time according to a time which is required for the comparison of the received signal levels in said level comparator.

Claim 19

A diversity receiving apparatus which is used in a digital communication system using a time division multiple access system for selecting and extracting a received signal of a good receiving state from a plurality of received signals, comprising: a plurality of receivers each of which is constructed by a detector for selecting the signal of a desired slot from the received signals of said time division multiple access system and a demodulator for demodulating the signal of the selected slot; a level comparator for comparing each of the received signal levels of the signal of the slot selected by each of said detectors of said plurality of receivers; a selector for selecting a demodulated signal from said demodulator of the receiver having the high received signal level on the basis of the comparison result in said level comparator and for outputting the selected demodulated signal; a data processor for storing the detection result of the past received signal level, for analyzing an aging change of the detection result of the received signal level, and for deciding a period of the comparison of the received signal levels corresponding to a period which is (n) times (n=1, 2, 3, . . . ) as long as a frame period of said time division multiple access system in accordance with an aging fluctuation amount of the received signal level; and a power controller for controlling a power supply to said plurality of receivers and said level comparator, wherein said power controller executes the power supply to all of said receivers and said level comparator in a head portion of the slot at which the reception is desired in accordance with the period of the comparison of the received signal levels decided by said data processor, continues only the power supply to the receiver having the high received signal level on the basis of the comparison result in said level comparator, and stops the power supply to the receivers other than the receiver having the high received signal level and to said level comparator.

Claim 20

A diversity receiving apparatus which is used in a digital communication system using a time division multiple access system for selecting and extracting a received signal of a good receiving state from a plurality of received signals, comprising: a plurality of receivers each of which is constructed by a detector for selecting the signal of a desired slot from the received signals of said time division multiple access system and a demodulator for demodulating the signal of the selected slot; a level comparator for comparing each of the received signal levels of the signal of the slot selected by each of said detectors of said plurality of receivers; a selector for selecting a demodulated signal from said demodulator of the receiver having the high received signal level on the basis of the comparison result in said level comparator and for outputting the selected demodulated signal; a data processor for storing the detection result of the past received signal level, for analyzing an aging change of the detection result of the received signal level, and for deciding a period of the comparison of the received signal levels corresponding to a period which is (n) times (n=1, 2, 3, . . . ) as long as a frame period of said time division multiple access system in accordance with an aging fluctuation amount of the received signal level; and a power controller for controlling a power supply to said plurality of receivers and said level comparator, wherein said power controller executes the power supply to all of said receivers and said level comparator in a head portion of the slot at which the reception is desired in accordance with the period of the comparison of the received signal levels decided by said data processor, continues only the power supply to the receiver having the high received signal level on the basis of the comparison result in said level comparator, and stops the power supply to the receivers other than the receiver having the high received signal level and to said level comparator.

Claim 21

An apparatus according to claim 16, wherein each of said receivers comprises a delay circuit which is provided at a post stage of said demodulator and delays the signal demodulated by said demodulator.

Claim 22

An apparatus according to claim 17, wherein said delay circuit has a delay time according to a time which is required for the comparison of the received signal levels in said level comparator.

Claim 23

An apparatus according to claim 16, wherein each of said receivers comprises a delay circuit which is provided between said detector and said demodulator and delays the signal selected by said detector.

Claim 24

An apparatus according to claim 19, wherein said delay circuit has a delay time according to a time which is required for the comparison of the received signal levels in said level comparator.