Space diversity receivers

Claim 2

A space diversity receiver for receiving broadcast signals comprising: a plurality of antenna connectors (11A, 11B, 11C, 11D), with each of which an antenna (12A, 12B, 12C, 12D) is to be connected, signal selecting means (47-54), 15A, 15B, 15C, 15D) for selecting one of signals obtained respectively from the antenna connectors (11A, 11B, 11C, 11D), signal processing circuit means (31-33) operative to produce an output signal based on a signal selected by the signal selecting means (47-54, 15A, 15B, 15C, 15D), signal sampling control means (46) operative to cause the signal selecting means (47-54, 15A, 15B, 15C, 15D) to perform a signal sampling operation through which the signals obtained respectively from the antenna connectors (11A, 11B, 11C, 11D) are selectively sampled for every predetermined short period to be supplied to the signal processing circuit means (31-33) during a predetermined specific period, antenna connector selecting means (42, 43) operative to compare in quality the output signals of the signal processing circuit means (30) obtained successively based on signals sampled through the signal sampling operation performed by the signal selecting means (47-54, 15A, 15B, 15C, 15D) with one another in order to select one of the antenna connectors (11A, 11B, 11C, 11D) through which a signal giving rise to the best output signal of the signal processing circuit means (30) is introduced during said predetermined specific period, and signal selecting control means (44) operative to cause the signal selecting means (47-54, 15A, 15B, 15C, 15D) to select the signal introduced through the antenna connector (11A, 11B, 11C, 11D) selected by the antenna connector selecting means (42, 43) during a period successive to said predetermined specific period, wherein the signal sampling control means (46) is further operative to elongate an interval between said predetermined specific periods so that a frequency of signal sampling operations in the signal selecting means (47-54, 15A, 15B, 15C, 15D) is reduced in response to increase in stability of the signal selected to be supplied to the signal processing circuit means (30) during said period successive to said predetermined specific period and to stop the signal sampling operation when the signal selected to be supplied to the signal processing circuit means (30) during said period successive to said predetermined specific period is sufficiently stabilized.

Claim 3

A space diversity receiver according to claim 2, wherein said signal selecting means (47-54, 15A, 15B, 15C, 15D) comprises a plurality of switching devices (15A, 15B, 15C, 15D) having respective first ends connected with the antenna connectors (11A, 11B, 11C, 11D), respectively, and respective second ends connected in common to the signal processing circuit means (30) and driving signal generator (47) for supplying each of said switching devices (15A, 15B, 15C, 15D) selectively with a driving signal

Claim 4

A space diversity receiver according to claim 3, wherein said switching device comprises a diode (15A-D) having one end connected through a capacitor (14A-D) with one of the antenna connectors (11A-D) and the other end connected through a capacitor (16) with the signal processing circuit means (30).

Claim 5

A space diversity receiver according to anyone of claims 2 to 4, wherein said antenna connector selecting means (42, 43) comprises a signal sampling circuit (42) for sampling each of the output signals of the signal processing circuit means (30) obtained based on the signals sampled through said signal sampling operation in the signal selecting means (47-54, 15A-D), respectively, and a comparator (43) for comparing in quality the output signals of the signal processing circuit means (30) sampled by said signal sampling circuit (42) with one another to supply the signal selecting control means (46) with a comparison output signal indicating said selected antenna connector (11A, 11B, 11C, 11D) through which the signal giving rise to the best output signal of the signal processing circuit means (30) is introduced.

Claim 6

A space diversity receiver for receiving broadcast signals comprising: a plurality of antenna connectors (11A-D), with each of which an antenna (12A-D) is to be connected, signal selecting means (47-54, 15A-D) for selecting one of signals obtained respectively from the antenna connectors (11A-D), signal processing circuit means (30) operative to produce an output signal based on a signal selected by the signal selecting means (47-54, 15A-D), signal sampling control means (46) operative to cause the signal selecting means (47-54, 15A-D) to perform a signal sampling operation through which the signals obtained respectively from the antenna connectors (11A-D are selectively sampled for every predetermined short period to be supplied to the signal processing circuit means (30) during a predetermined specific period, antenna connector selecting means (42, 43) operative to compare in quality the output signals of the signal processing circuit means (30) obtained successively based on signals sampled through the signals sampling operation performed by the signal selecting means (47-54, 15A-D) with one another in order to select one of the antenna connectors (11A-D) through which a signal giving rise to the best output signal of the signal processing circuit means (30) is introduced during said predetermined specific period, signal selecting control means (44) operative to cause the signal selecting means (47-54, 15A-D) to select the signal introduced through the antenna connector (11A-D) selected by the antenna connector selecting means (42, 43) during a period successive to said predetermined specific period, and antenna occupancy checking means (45, 13A-D) operative to detect one or more of the antenna connectors (11A-D with which the antenna (12A-D) is not connected and to cause the signal sampling operation in the signal selecting means (47-54, 15A-D) not to sample the signal obtained from the antenna connector (11A-D) detected said antenna occupancy checking means (45, 13A-D).

Claim 7

A space diversity receiver according to claim 6, wherein said signal selecting means (47-54, 15A-D) comprises a plurality of switching devices (15A-D) having respective first ends connected with the antenna connectors (11A-D), respectively, and respective second ends connected in common to the signal processing circuit means (30) and driving signal generator (47) for supplying each of said switching devices (15A-D) selectively with a driving signal.

Claim 8

A space diversity receiver according to claim 7, wherein said switching device comprises a diode (15A-D) having one end connected through a capacitor (14A-D) with one of the antenna connectors (11A-D) and the other end connected through a capacitor (16) with the signal processing circuit means (30).

Claim 9

A space diversity receiver according to anyone of claims 6 to 8, wherein said antenna connector selecting means (42, 43) comprises a signal sampling circuit (42) for sampling each of the output signals of the signal processing circuit means (30) obtained based on the signals sampled through said signal sampling operation in the signal selecting means (47-52, 15A-D), respectively, and a comparator (43) for comparing in quality the output signals of the signal processing circuit means (30) sampled by said signal sampling circuit (42) with one another to supply the signal selecting control means (46) with a comparison output signal indicating said selected antenna connector (11A-D) through which the signal giving rise to the best output signal of the signal processing circuit means (30) is introduced.

Claim 10

A space diversity receiver according to anyone of claims 6 to 9, wherein antenna occupancy checking means (45, 13A-D) comprises a plurality of antenna connection detecting means (13A-D) formed to include the antenna connectors (11A-D), respectively, and each provided for producing an antenna detection output signal having a first level when the antenna (12A-D) is connected with the antenna connector (11A-D) included therein and a second level different from said first level when the antenna (12A-D) is not connected with the antenna connector (11A-D) included therein, and unoccupied antenna connector detecting means (45) for detecting an unoccupied antenna connector (11A-D) with which the antenna (12A-D) is not connected based on the antenna detection output signal and supplying the signal sampling control means (46) with a detection output signal indicating antenna occupancy on the antenna connectors (11A-D).

Claim 11

A space diversity receiver according to anyone of claims 6 to 9, wherein said antenna occupancy checking means (45, 13A-D) comprises signal evaluating means (61) operative to evaluate a predetermined signal component (SV, SH) contained in each of the output signals (VD) of the signal processing circuit means (30) obtained successively based on the signals sampled through the signal sampling operation performed by the signal selecting means (42-54, 15A-D) for detecting an unoccupied antenna connector (11A-D) with which the antenna (12A-D) is not connected based on results of evaluation for said predetermined signal components (SV, SH) and to supply the signal sampling control means (46) with a control signal indicating antenna occupancy on the antenna connectors (11A-D).