摘要:
A receiver in a communication system is coupled to a transmission channel for receiving communication signals transmitted over a transmission channel. The receiver includes signal receiving electronics for receiving communication signals directed to the receiver. The receiver also includes a controller, responsive to the receipt of a communication signal by the signal receiving electronics, to provide an enunciator enable signal, and a clock signal generator for generating a clock signal. The receiver further includes an enunciator coupled to the clock signal generator, for producing an electronic sound signal. The enunciator includes a volume control module for receiving a first periodic signal and providing a volume control signal. The enunciator also includes a divider for receiving the clock signal and providing a corresponding output signal having a frequency corresponding to the frequency of the clock signal frequency divided by a divider value. The enunciator further includes a tone control module coupled to the divider, for providing a tone control signal having a specified frequency and overtone pattern, and a modulator for modulating the third periodic signal by the second periodic signal to provide an electronic sound signal.
摘要:
The current disclosure is directed toward part or all digital phase lock loop circuits, particularly those containing divide by N circuits between the voltage controlled oscillator and the phase detector. These divide by N circuits many times contain long logic count down chains. In power sensitive applications the amount of power dissipated by these divide by N circuits may be significant. The current disclosure is directed to apparatus and methods of cycling these divide by N circuits between enabled and disabled to conserve power. The changing of the enabled/disabled frequency and the duty cycle of the disabling of the divider is contemplated, as are the various ancillary factors that might be considered in determining this frequency and duty cycle. Stabilization of the loop is considered as is the changing of gain of the phase lock loop in order to improve operation as the dividers are enabled and disabled.
摘要:
Apparatus and methods for adjustment of spectral signal characteristics in polar modulators are described. A composite signal detection circuit is configured to detect when a signal trajectory of a composite signal provided to the polar modulator passes near the origin of a complex plane associated with the composite signal, and then adjusts the composite signal to pass through the origin. A spectral adjustment circuit is described to adjust AM and FM or PM components of the composite signal to reduce the deviation of an FM component of the composite signal.
摘要:
A cancellation system that delays received Global Positioning System (“GPS”) signals and cancels less than all of the received GPS signals from the delayed version of the received GPS signals. A delay circuit produces a delayed version of the received GPS signals and a demodulator and despreader unit produces a demodulated and despread GPS signal corresponding to one of the received GPS signals. A respreader and remodulator unit produces a remodulated and respread GPS signal from the demodulated and despread GPS signal and a combiner produces a combined GPS signal from the delayed version of the received GPS signals and the remodulated and respread GPS signal. The cancellation system and method may also store the received GPS signals and cancel less than all the received GPS signals from the stored version of the received GPS signals.
摘要:
An apparatus for providing a two point phase/frequency modulation system is disclosed herein. The apparatus includes a first network configured to introduce an offset to center a signal applied to a VCO. The apparatus further includes a second network configured to set a gain of the VCO. A phase tracking network is configured to dynamically adjust the offset and the gain.
摘要:
An apparatus providing a phase/frequency modulation system is disclosed herein. The apparatus includes a first circuit configured to introduce an offset to center a signal applied to a VCO. The apparatus further includes a second circuit configured to set a gain of the VCO. A frequency tracking network is configured to dynamically adjust one or both of the offset and the gain.
摘要:
A receiver in a communication system is coupled to a transmission channel for receiving communication signals transmitted over a transmission channel. The receiver includes signal receiving electronics for receiving communication signals directed to the receiver. The receiver also includes a controller, responsive to the receipt of a communication signal by the signal receiving electronics, to provide an enunciator enable signal, and a clock signal generator for generating a clock signal. The receiver further includes an enunciator coupled to the clock signal generator, for producing an electronic sound signal. The enunciator includes a volume control module for receiving a first periodic signal and providing a volume control signal. The enunciator also includes a divider for receiving the clock signal and providing a corresponding output signal having a frequency corresponding to the frequency of the clock signal frequency divided by a divider value. The enunciator further includes a tone control module coupled to the divider, for providing a tone control signal having a specified frequency and overtone pattern, and a modulator for modulating the third periodic signal by the second periodic signal to provide an electronic sound signal.
摘要:
A cancellation system that delays the received signals and cancels less than all the received signals from the delayed version of the received signals and a demodulator and despreader unit produces a demodulated and de-spreader and remodulator unit produces a remodulated and respread signal from the demodulated and despread signal with a combiner that produces a combined signal from the delayed version of the received signals and the remodulated and respread signal to identify a low power signal.