Abstract: A system for providing a first signal to a flip circuit and receiving a second signal from the flip circuit over an electrical path adapted for use with a keypad having a keypad lighting circuit. The system includes a first circuit for providing the first signal to the flip circuit via a first electrical path, the first signal having alternating first and second states. A second circuit generates a second signal. A third circuit receives the second signal via the first electrical path. The second signal is received during the second state of the first signal. In a more specific embodiment, the first and second states are continuously alternating states. The first signal provides power to the flip circuit when the first signal is in the first state. The first circuit further includes a signal generator for adjusting a duty cycle of the first signal. The signal generator includes a voltage source, a switching circuit connected to the voltage source, and a control circuit connected to the switching circuit.

Abstract: A wireless communication device, comprising one or more intra-device modules, an internet protocol (IP) router for providing inter-device connectivity between a host and the intra-device modules, and one or more transport mechanisms, for coupling the IP router to the host. One or more intra-device modules are accessed via a standard internetwork protocol as if the intra-device modules were local servers.

Abstract: A system for reducing receiver power consumption in communication system having a transmitter and one or more receivers schedules periodic messages in "slots." Each receiver is assigned a slot during which it monitors the transmissions. The transmitter transmits messages to the receiver only during the assigned slots. The receiver is in an "active state" during its assigned slot. It may remain in the active state after its assigned slot if the message requires the receiver to perform additional actions. During the "inactive state," which is the time period between successive occurrences of its assigned slot, the receiver may perform any action not requiring coordination with the transmitter. It may conserve power during this time by removing power from one or more components such as those used for monitoring the transmissions. At a time during the inactive state shortly before the assigned slot, the receiver applies power to these components and performs initializations.

Abstract: The process and apparatus of the present invention limits the output power of a radiotelephone, operating in a cellular system in the preferred embodiment. This ensures the transmitted sidebands and synthesizer phase noise remains within a certain specification. This is accomplished by power detection and a correction accumulator that together generate a gain control signal by limiting the gain adjustment to a maximum value, even when the cell site communicating with the radiotelephone is sending power turn-up commands to the radiotelephone. This process includes dynamically correcting the output level of the transmitter due to gain variations in the transmitter stages or gain control elements.

Abstract: A system for reducing receiver power consumption in communication system having a transmitter and one or more receivers schedules periodic messages in "slots." Each receiver is assigned a slot during which it monitors the transmissions. The transmitter transmits messages to the receiver only during the assigned slots. The receiver is in an "active state" during its assigned slot. It may remain in the active state after its assigned slot if the message requires the receiver to perform additional actions. During the "inactive state," which is the time period between successive occurrences of its assigned slot, the receiver may perform any action not requiring coordination with the transmitter. It may conserve power during this time by removing power from one or more components such as those used for monitoring the transmissions. At a time during the inactive state shortly before the assigned slot, the receiver applies power to these components and performs initializations.

Abstract: A method and apparatus for converting phase data into amplitude data. Input phase data is divided into upper and lower phase increments using an input splitter which can also fold in quadrant data. One or more storage elements, such as sine and cosine ROMs, are connected to the input splitter and generate an amplitude, which forms one of a plurality of series terms, and first and second derivatives of the amplitude in response to the upper phase increment. The first derivative and lower phase increment are multiplied together in a digital multiplier to produce a second series term. A third series term comprising a product of the amplitude and lower phase increment squared, is generated by a term generator connected to the splitter and to the storage element. The term generator can comprise elements such as a ROM addressable by the lower phase increment and the amplitude.

Abstract: A method and apparatus for reducing spurious output noise in digital frequency synthesizers employing sine amplitude converters connected to Digital-to-Analog converters to generate analog waveforms from sine amplitude data. Random or pseudorandom numbers having a value equal to or less than plus or minus one-half of a minimum quantization step or value change for the sine amplitude data are generated and added to the sine amplitude data with the resulting sum being transferred to the Digital-to-Analog converter. In one embodiment, a summation circuit is connected between an output of the sine function converter and an input of the Digital-to-Analog converter and also has a second input connected to a pseudorandom number generator which provides Pseudorandom numbers varying in value over a range of .+-.1/2.sup.n+1 times a least significant step value, or bit for base 2, of a corresponding Digital-to-Analog input data value where n is greater than or equal to 1.