Spatial diversity receiving device and input channel switching method

A spatial diversity receiving device for use in a telemetry monitoring or testing system including a plurality of antennae, the receiving device comprising:

• a main control circuit and at least one receiving channel including a RF selective switch,
• wherein the main control circuit controls the RF selective switch, so as to select one of the plurality of input signals coming from the plurality of antennae and send that signal to a receiving module of the receiving channel, which receiving module comprises a received signal strength indication unit for outputting a RSSI value corresponding to an input signal and sending that value to the main control circuit;
• wherein the main control circuit further receives the data transferred to the receiving module;
• wherein the main control circuit waits and selects a predetermined occasion to perform the following steps, wherein the predetermined occasion is selected from a group comprising at least one of an interframe space between two data frames being transferred and a time at which a transfer of one data frame completes;
• wherein the main control circuit records the RSSI value of the current signal output by the received signal strength indication unit as an original RSSI value;
• wherein the main control circuit selects an input signal from another antenna as a currently selected antenna, and sends that signal to the receiving channel;
• and
• wherein the main control circuit reads the current RSSI value output by the received signal strength indication unit, and then determines whether the signal to be input into the receiving channel is to come right along from the currently selected antenna, or is to be switched back to the previously selected antenna.