EP0440239A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Antenna selection diversity reception apparatus
Assignee: Mitsubishi Electric Corp
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Filing: 1991-01-31
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Granted: —
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Expires: 2011-01-31
Abstract
Abstract An antenna selection decision system detects the level of the TDM burst immediately preceding to the TDM burst of the user's own channel and decides, on the basis of the detected level, to use the antenna selection diversity method or another selection criterion. When the other selection criterion is selected, the antenna which should receive the next TDM burst of the user's own channel is selected depending on the level of TDM burst of the user's own channel.
Inventors
- 👤 Hideshi C/O Tsushin System Kenkyousho Murai
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 20:01
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/02; H04B7/04; H04B7/08; H04B7/0802; H04B7/0805; H04B7/0808; H04B7/0811
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
249 words
An antenna selection diversity reception apparatus for a digital vehicle communication system according to a TDM system, comprising a plurality of antennas for receiving TDM bursts of digital modulation signals, an antenna switching system for selecting and switching said antenna, a reception system for providing the TDM bursts received by the antenna which has been selected by said antenna switching system with high frequency amplification, frequency conversion and intermediate frequency amplification, a demodulation system for demodulating transmission data from the signal output from said reception system, and an antenna selection decision system for generating an antenna selection signal which controls said antenna switching system in accordance with the signal output from said reception system with branch switching being executed in accordance with TDM bursts, having characteristic in that said antenna selection decision system comprises: a level detector for detecting the level of the signal provided from said reception system; a memory for storing the level detected by said level detector; a computing means for computing the respective levels which have been stored in said memory; a comparator for comparing the result of the computation effected by said computing means with a numerical value which has been provided in advance and for generating a control signal; and an antenna selection decision means for generating an antenna selection signal which controls selection of said antenna in accordance with the control signal from said comparator to said antenna selection decision means, to provide said antenna selection signal to said antenna switching system.
Claim 2
Dependent Claim
77 words
An antenna selection diversity reception apparatus as claimed in Claim 1 wherein said level detector detects the levels of the signals which are included in the TDM burst immediately preceding to the TDM burst of the channel allocated to the apparatus and respectively received by said plural antennas, and the level of the signal which is included in the TDM burst of the channel allocated to the apparatus and received by the antenna which has been selected.
Claim 3
Dependent Claim
99 words
An antenna selection diversity reception apparatus as claimed in Claim 2 wherein said comparator generates a first control signal indicating that antenna selection is effected based on said levels of the signals included in the immediately preceding TDM burst, when said result of the computation is equal to or more than a given value, and generates a second control signal indicating that antenna selection is effected on the basis of said level of the signal included in the TDM burst of the channel allocated to the apparatus, when said result of the computation is less than said given value.
Claim 4
Dependent Claim
112 words
An antenna selection diversity reception apparatus as claimed in Claim 3 wherein said antenna selection decision means responds to said first control signal to generate a first antenna selection signal indicating a switch to the antenna which has the maximum level of the signal included immediately preceding TDM burst, and responds to said second control signal to compare said level of the signal included in the TDM burst of the channel allocated to the apparatus and received by the antenna which has been selected, with a predetermined level, and, if the former is less than the predetermined level, to generate a second antenna selection signal indicating a switch to the other antenna.
Claim 5
Dependent Claim
24 words
An antenna selection diversity reception apparatus as claimed in Claim 1 wherein said computing means computes the mean level value of said respective levels.
Claim 6
Dependent Claim
24 words
An antenna selection diversity reception apparatus as claimed in Claim 5 wherein said mean level values are the mean values of said respective levels.
Claim 7
Dependent Claim
169 words
An antenna selection diversity reception apparatus for a digital vehicle communication system according to TDM method, comprising plural antennas for receiving TDM bursts of digital modulation signals, an antenna switching means for switching said antennas, a reception means for receiving the TDM bursts received by the antenna which has been selected by said antenna switching means, and an antenna selection decision system for selecting the antenna to be connected to said reception means with branch selection being executed in accordance with TDM bursts, having characteristic in that said antenna selection decision system including the level detecting means for detecting the levels of the signals which are included in the TDM burst of the channel allocated to the apparatus and the TDM burst immediately preceding thereto and are received by said antennas, and an antenna selection decision means for generating an antenna selection signal on the basis of the levels detected by said level detecting means; said antenna switching means responding to said antenna selection signal to switch said antennas.
Claim 8
Dependent Claim
49 words
An antenna selection diversity reception apparatus as claimed in Claim 7 wherein said antenna selection decision system further includes a calculating means for calculating mean level values based on the detected levels; and said antenna selection decision means generates said antennas selection signal based on said mean level values.
Claim 9
Dependent Claim
150 words
An antenna selection diversity reception apparatus as claimed in Claim 7 wherein said antenna selection decision system further includes a comparing means for comparing the detected level of the signal included in said immediately preceding TDM burst with a predetermined level; and said antenna selection decision means compares the detected level of the signal included in said TDM burst of the channel allocated to the apparatus and received by the antenna which has been selected, with another predetermined level, when the result obtained from said comparing means is that the detected level of the signal included in said immediately preceding TDM burst is less than said predetermined level, and said antenna selection decision means generating an antenna selection signal indicating a switch to another antenna, when said detected level of the signal in said TDM burst of the channel allocated to the apparatus is less than said another predetermined level.
References Cited (Backward Citations)
No citation records indexed.
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