Method and apparatus for controlling switched antenna diversity systems

Claim 1

A method for selecting one of at least two antennas in a communication unit, the method comprising the steps of: receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal transmitted in a communications format comprising a plurality of bits having bit transitions; generating a reference clock signal based on the received signal; determining whether some of the bit transitions fall within a predefined time window corresponding to each transition, the predefined time window is determined by the reference clock signal; determining the quality of the incoming signal based on the number of bit transitions that fall outside of the predefined window; selecting for a subsequent receiving period one of the at least two antennas in response to the quality of the incoming signal; and wherein the step of determining the quality of the incoming signal, comprises the sub-steps of: determining the total number of bit transitions that have occurred in the receive period; determining the number of bit transitions during the receiving period which have fallen outside of the predefined window; and calculating the percentage of bit transitions which fall outside of the predefined window from the total number of bit transitions.

Claim 2

A method for selecting one of at least two antennas in a communication unit, the method comprising the steps of: receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal transmitted in a communications format comprising a plurality of bits having bit transitions; generating a reference clock signal based on the received signal; determining whether some of the bit transitions fall within a predefined time window corresponding to each transition, the predefined time window is determined by the reference clock signal; determining the quality of the incoming signal based on the number of bit transitions that fall outside of the predefined window; selecting for a subsequent receiving period one of the at least two antennas in response to the quality of the incoming signal; and wherein the step of determining the quality of the incoming signal, comprises the sub-steps of: determining the total number of bit transitions that have occurred in the receive period; determining the number of bit transitions during the receiving period which have fallen outside of the predefined window; and calculating the percentage of bit transitions which fall outside of the predefined window from the total number of bit transitions.

Claim 6

A method for selecting one of at least two antennas in a communication unit, the method comprising the steps of: receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal transmitted in a communications format comprising a plurality of bits having bit transitions; generating a reference clock signal based on the received signal; determining whether some of the bit transitions fall within a predefined time window corresponding to each transition, the predefined time window is determined by the reference clock signal; determining the quality of the incoming signal based on the number of bit transitions that fall outside of the predefined window; selecting for a subsequent receiving period one of the at least two antennas in response to the quality of the incoming signal; and maintaining the currently selected antenna when the currently selected antenna has been selected within a predetermined period of time.

Claim 7

A method for selecting one of at least two antennas in a communication unit, the method comprising the steps of: receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal transmitted in a communications format comprising a plurality of bits having bit transitions; generating a reference clock signal based on the received signal; determining whether some of the bit transitions fall within a predefined time window corresponding to each transition, the predefined time window is determined by the reference clock signal; determining the quality of the incoming signal based on the number of bit transitions that fall outside of the predefined window; selecting for a subsequent receiving period one of the at least two antennas in response to the quality of the incoming signal; and maintaining the currently selected antenna when the currently selected antenna has been selected within a predetermined period of time.

Claim 8

A method for selecting one of at least two antennas in a communication unit, the method comprising the steps of: receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal transmitted in a distal communications format comprising at least one bit having a bit transition; generating a reference clock signal based on the received signal, the reference clock signal having at least one level change; determining whether the at least one bit transition in the receiving period falls within a predefined time window determined by the least one reference clock level change; determining the quality of the incoming signal based on whether the at least one bit transition falls within the predefined time window; selecting for a subsequent receiving period one of the at least two antennas when the at least one bit transition has fallen outside of the predefined window; determining the length of time the presently selected antenna has been selected; and maintaining the currently selected antenna when the currently selected antenna had been selected within a predetermined period of time.

Claim 9

A method for selecting one of at least two antennas in a communication unit, the method comprising the steps of: receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal transmitted in a distal communications format comprising at least one bit having a bit transition; generating a reference clock signal based on the received signal, the reference clock signal having at least one level change; determining whether the at least one bit transition in the receiving period falls within a predefined time window determined by the least one reference clock level change; determining the quality of the incoming signal based on whether the at least one bit transition falls within the predefined time window; selecting for a subsequent receiving period one of the at least two antennas when the at least one bit transition has fallen outside of the predefined window; determining the length of time the presently selected antenna has been selected; and maintaining the currently selected antenna when the currently selected antenna had been selected within a predetermined period of time.

Claim 11

A method for selecting one of at least two antennas in a communication unit, the method comprising the steps of: receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal transmitted in a digital communications format comprising at least one bit having a bit transition; generating a reference clock signal based on the received signal, the reference clock signal having at least one level change; determining whether the at least one bit transition in the receiving period falls within a predefined time window determined by the least one reference clock level change; determining the quality of the incoming signal based on whether the at least one bit transition falls within the predefined time window; selecting for a subsequent receiving period one of the at least two antennas when the at least one bit transition has fallen outside of the predefined window; and selecting for a subsequent receiving period one of the at least two antennas when two or more bit transitions have fallen within the predefined window.

Claim 12

A method for selecting one of at least two antennas in a communication unit, the method comprising the steps of: receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal transmitted in a digital communications format comprising at least one bit having a bit transition; generating a reference clock signal based on the received signal, the reference clock signal having at least one level change; determining whether the at least one bit transition in the receiving period falls within a predefined time window determined by the least one reference clock level change; determining the quality of the incoming signal based on whether the at least one bit transition falls within the predefined time window; selecting for a subsequent receiving period one of the at least two antennas when the at least one bit transition has fallen outside of the predefined window; and selecting for a subsequent receiving period one of the at least two antennas when two or more bit transitions have fallen within the predefined window.

Claim 13

An apparatus for selecting one of at least two antennas in a communication unit for use in a wireless communication system, the apparatus comprising: receiver means for receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal comprising a communications format comprising a plurality of data bits having bit transitions; antenna switch coupled to the receiver means and to the at least two antennas for coupling a selected one of the at least two antennas to the receiver means; reference clock generator coupled to the receiver for generating a reference signal based on the received signal; determination means coupled to the reference clock generator and receiver means for determining when some of the bit transitions fall within predefined time windows, one predefined time window corresponding to each of the bit transitions; a controller coupled to the receiver means for determining the quality of the incoming signal based on the number of bit transitions that fall within the predefined windows; the antenna switch responsive to the controller for selecting for a subsequent receive period one of the at least two antennas in response to the quality determination performed by the controller; and the controller maintains the currently selected antenna as the antenna coupled to the receiver means when the currently selected antenna has been selected within a predetermined period of time.

Claim 14

An apparatus for selecting one of at least two antennas in a communication unit for use in a wireless communication system, the apparatus comprising: receiver means for receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal comprising a communications format comprising a plurality of data bits having bit transitions; antenna switch coupled to the receiver means and to the at least two antennas for coupling a selected one of the at least two antennas to the receiver means; reference clock generator coupled to the receiver for generating a reference signal based on the received signal; determination means coupled to the reference clock generator and receiver means for determining when some of the bit transitions fall within predefined time windows, one predefined time window corresponding to each of the bit transitions; a controller coupled to the receiver means for determining the quality of the incoming signal based on the number of bit transitions that fall within the predefined windows; the antenna switch responsive to the controller for selecting for a subsequent receive period one of the at least two antennas in response to the quality determination performed by the controller; and the controller maintains the currently selected antenna as the antenna coupled to the receiver means when the currently selected antenna has been selected within a predetermined period of time.

Claim 15

An apparatus for selecting one of at least two antennas in a communication unit for use in a wireless communication system, the apparatus comprising: receiver means for receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal comprising a communications format comprising a plurality of data bits having bit transitions; antenna switch coupled to the receiver means and to the at least two antennas for coupling a selected one of the at least two antennas to the receiver means; reference clock generator coupled to the receiver for generating a reference signal based on the received signal; determination means coupled to the reference clock generator and receiver means for deterring when some of the bit transitions fall within predefined time windows one predefined time window corresponding to each of the bit transitions; a controller coupled to the receiver means for determining the quality of the incoming signal based on the number of bit transitions that fall within the predefined windows; the antenna switch responsive to the controller for selecting for a subsequent receive period one of the at least two antennas in response to the quality determination performed by the controller; the controller maintains the currently selected antenna as the antenna coupled to the receiver means when the currently selected antenna has been selected within a predetermined period of time; and the apparatus is a second generation cordless telephone (CT2) base station.

Claim 16

An apparatus for selecting one of at least two antennas in a communication unit for use in a wireless communication system, the apparatus comprising: receiver means for receiving during a receiving period a signal from a currently selected one of the at least two antennas, the signal comprising a communications format comprising a plurality of data bits having bit transitions; antenna switch coupled to the receiver means and to the at least two antennas for coupling a selected one of the at least two antennas to the receiver means; reference clock generator coupled to the receiver for generating a reference signal based on the received signal; determination means coupled to the reference clock generator and receiver means for deterring when some of the bit transitions fall within predefined time windows one predefined time window corresponding to each of the bit transitions; a controller coupled to the receiver means for determining the quality of the incoming signal based on the number of bit transitions that fall within the predefined windows; the antenna switch responsive to the controller for selecting for a subsequent receive period one of the at least two antennas in response to the quality determination performed by the controller; the controller maintains the currently selected antenna as the antenna coupled to the receiver means when the currently selected antenna has been selected within a predetermined period of time; and the apparatus is a second generation cordless telephone (CT2) base station.