| CPC H04B 7/06 (2013.01) [H04B 7/0404 (2013.01)] | 20 Claims |

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1. A communication device comprising:
a communications subsystem having more than one transmit chains comprising at least a first transmit chain and a second transmit chain configurable to perform transmit diversity; and
a controller communicatively coupled to the communications subsystem, and which:
in response to determining a requirement to increase transmit power of an uplink signal that is more than an individual capacity of either one of the first and the second transmit chains:
sequentially configures the first and the second transmit chains to transmit the uplink signal with one of: (i) cyclic delay diversity (CDD); or (ii) linear delay diversity (LDD) that delays the uplink signal transmitted by the second transmit chain with each of more than one phase shift or time delay values;
transmits the uplink signal using transmit diversity with sequentially changed phase shift or time delay values for the one of CCD or LDD;
monitors at least one of a direct measure and an indirect measure of uplink signal quality at a network node for each of the sequentially changed phase shift or time delay values;
determines an optimal phase shift or time delay value for current channel conditions of the more than one phase shift or time delay values associated with a higher measure of uplink signal quality than other ones of the more than one phase shift or time delay values; and
transmits the uplink signal via transmit diversity using the optimal phase shift or time delay value for the one of CDD or LDD.
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