Patent ID: 7822397
Filing Date: 2010-10-26
Classification: H04B

Abstract:
1. A receiver circuit, the circuit comprising: a radio frequency (RF) section that includes an amplifier configured to be coupled to an antenna and first and second mixers coupled to an output of the amplifier to recover first and second data channels, respectively; a baseband section that includes a first baseband block with an input coupled to an output of the first mixer and a second baseband block with an input coupled to an output of the second mixer; a demodulator having a first input coupled to an output of the first baseband block and a second input coupled to an output of the second baseband block; a data and clock recovery circuit having an input coupled to an output of the demodulator; a data quality detector (DQD) circuit configured to indicate the presence or absence of a packetized data transmission at the output of the demodulator by asserting a DQD signal only upon detection of the packetized data transmission at the output of the demodulator and by not asserting the DQD signal when no packetized data transmission is detected at the output of the demodulator, the DQD circuit having a first input coupled to the output of the first baseband block and a second input coupled to the output of the second baseband block, where the DQD circuit is configured to detect the presence or absence of the packetized data transmission at the output of the demodulator by: a controller configured to control a receive frequency of the RF section and monitor the DQD signal, where the controller is operable to frequency hop through each of a plurality of channel frequencies and, for each channel frequency, wait a first preset period of time after changing the channel frequency for the DQD signal to be asserted and, if the DQD signal is not asserted within the first preset period of time, resume frequency hopping and, if the DQD is asserted, maintain a current channel frequency in order to receive a data packet of the detected packetized data transmission.