Abstract:
A technique for adding a new information rate to a legacy physical interface of a communications system includes using a rate switch packet including a distinct rate select start-of-frame delimiter that indicates a newly defined physical interface packet. The rate switch packet uses the same modulation scheme as a base rate packet (e.g., a packet using an information rate defined by a standard communications protocol) and the same preamble pattern as the base rate packet. The preamble length of the rate switch packet can be the same as or different from the preamble length of the base rate packet. An embodiment uses antenna diversity by selecting the antenna in the rate switch packet and using the selected antenna to receive an adjusted rate packet. Additional rate switch start-of-frame delimiters can be used to indicate more than one adjusted rate packet, e.g., to support multiple adjusted information rates.
Abstract:
A radio frequency (RF) receiver comprises an analog receiver, a digital signal processor, a clock synthesizer, and a microcontroller. The analog receiver has an input for receiving an RF input signal, and an output for providing a digital intermediate frequency (IF) signal. The digital signal processor has a first input for receiving the digital IF signal, a second input for receiving a clock signal, and a signal output for providing an IF output signal. The clock synthesizer has an input for receiving a clock control signal, and an output for providing the clock signal. The a microcontroller has an input for receiving a channel selection signal, wherein the microcontroller provides the clock control signal to control a frequency of the clock signal dynamically in response to a channel selection input to place a sub-harmonic at a tolerable frequency of a selected channel.