| 摘要 |
An antenna switching arrangement is disclosed for an rf transceiver which may operate at 2.4GHz or 5GHz. It has been recognised that antenna diversity, if required, is needed only in the receive mode and not in the transmit mode. The resulting circuit comprises a first antenna 113 connected to the common terminal (pole) of a first spdt switch 209, a second antenna 115 connected to the common terminal of a second spdt switch 213, the first and second switches being connected to respective transmitters 101 and 103. The first and second switches are connected to a third spdt switch 211 which in turn connects the antennas to a common receiver 105. This circuit connects each transmitter to its respective antenna through a path which includes only one transmit-receive switch, and thus reduces transmit power losses in comparison to prior art arrangements (fig. 1) in which the transmitter signal must pass through more than one switch. |
