Method and apparatus for improving receiver performance in a land mobile communications system
First Claim
1. A method for improving the signal quality of signals received at a base station including the steps of:
- (a) receiving messages concurrently on a plurality of directional antennas, at least one of the antennas having a main lobe that is off axis from the main lobe of at least one other such antenna,(b) determining whether any of the concurrently received messages are the same;
(c) discarding all but one of the messages determined to be same; and
(d) communicating the undiscarded messages to an external device.
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0 Petitions
Accused Products
Abstract
A method and apparatus for improving the signal-to-interference ratio and signal-to-noise ratio of a signal transmitted on a reverse channel from a mobile transmitter in a land mobile communications system by using a sectored cell in which the same channel is received by each sector of the cell. Each directional antenna is coupled to a unique associated receiver tuned to the same frequency or frequencies as the other receivers associated with each other directional antenna within the same sectored cell. Depending upon the location of the mobile end system with respect to the antenna pattern of each directional antenna, each signal will typically be redundantly received over more than one, but less than all, of the antennas. In accordance with the present invention, only one of the received signals is to be communicated from the base station to an intermediate system and all others are to be discarded. If multiple copies of the same message are received, then the control computer couples only one such copy to the intermediate system and discards each of the others.
58 Citations
39 Claims
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1. A method for improving the signal quality of signals received at a base station including the steps of:
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(a) receiving messages concurrently on a plurality of directional antennas, at least one of the antennas having a main lobe that is off axis from the main lobe of at least one other such antenna, (b) determining whether any of the concurrently received messages are the same; (c) discarding all but one of the messages determined to be same; and (d) communicating the undiscarded messages to an external device. - View Dependent Claims (12)
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2. A base station including:
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(a) at least two directional antennas having their main lobes off axis from one another; (b) at least two receivers, each receiver associated with, and coupled to, a corresponding one of the at least two antennas each receiver tuned to the same receive channel for receiving messages; and (c) a control computer, coupled to each of the receivers, for receiving messages from each receiver and determining whether the received messages are duplicative. - View Dependent Claims (3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
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23. A base station, including:
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(a) at least two directional antennas having their main lobes off axis from one another; (b) at least two receivers, each receiver associated with, and coupled to, a corresponding one of the at least two antennas, each receiver tuned to the same receive channel for receiving messages; and (c) a control computer, coupled to each of the receivers, for receiving in the control computer the received messages from each receiver, detecting whether said messages are duplicates, and selecting from among the duplicate messages received within a predetermined range of times, one of the received duplicate messages to be coupled to an external device. - View Dependent Claims (24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39)
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Specification