Uniden America Corporation

Hughes Electronics Corporation

Hassan Zamat

Brian K Fair

Kumud Patel

Kumud S Patel

A power measurement circuit, suitable for use in communications devices, is provided in which first and second signals derived from the signal of interest are passed through a multiplier, and the output of the multiplier is passed through a filter. In one embodiment, the filter provides a signal substantially representative of or relating to the DC component of the signal output from the multiplier. In another embodiment, the filter provides a signal substantially representative of or relating to the average power of the signal of interest. Advantageously, in one embodiment, the signal output from the filter bears a substantially linear relationship to the average power of the signal of interest over a desired region of operation. In a second embodiment, the signal output from the filter is advantageously substantially frequency invariant over a desired region of operation.

Power measurement circuit

A system and method for controlling an antenna arrangement including a plurality of antennas employed in, for example, a user terminal of a communications network, to provide a selected antenna pattern from among different antenna patterns based on, for example, the strength of a communications signal being received by the antenna arrangement of the user terminal, in order to satisfy desired gain and beamwidth requirements. The system and method can employ a switch that can be manually switched to control the antenna arrangement to provide the selected antenna pattern. The switch also can include a plurality of diodes that are controlled automatically or by a manual switch to select the antenna pattern. The plurality of antennas can be selectively activated and deactivated to provide the selected antenna pattern. Also, the plurality of antennas can be stacked vertically in relation to each other, or can include a first antenna and a second antenna disposed within said first antenna. Furthermore, the antenna arrangement can include at least one quadrifilar antenna or at least one octifilar antenna.

System and method for switching between different antenna patterns to satisfy antenna gain requirements over a desired coverage angle

A communications device determines transmitted signal power by providing the transmitted signal to a signal strength indication (SSI) processor that detects voltage of the transmitted signal and determines signal power of the transmitted signal during normal operation by searching a calibration table of the SSI processor and correlating the detected transmitted signal voltage to stored signal power values. The calibration table is constructed by providing transmitted signals to the SSI processor during a calibration phase of operation, detecting the transmitted signal power, and storing the transmitted signal voltage level with the detected transmitted signal power, for a plurality of transmitted signals. Thus, the SSI processor combines the function of a conventional RSSI processor and also performs measurement of the transmitted signal power.

Detection of transmitted power using received signal strength circuitry

A mobile communication device comprising a handset achieves gain control of a received signal by adjusting gain of the received signal based on A/D converter samples of the received signal, rather than on power I,and Q,calculations of the received signal. The device processes a received signal and adjusts its gain by first setting signal gain to a maximum level, then providing the amplified received signal to an analog-to-digital converter (ADC) that produces a predetermined number of ADC signal sample values in a single cycle of an estimated signal frequency of the received signal. Setting the signal gain to a maximum initial level will cause a number of ADC signal sample values to have full scale magnitude, indicating saturation of the ADC. Next, the device continues processing by determining the number of ADC signal sample values that indicate full scale magnitude of the received signal within a signal cycle, and then adjusts the signal gain from the maximum level that causes the number of ADC signal sample values that indicate full scale magnitude to be above a predetermined saturation threshold so as to reduce the signal gain until the saturation threshold is not exceeded. In this way, a communications device constructed in accordance with the invention provides improved signal gain control and associated processing performance with minimized costs.

Adjusting gain in a receiver using received signal sample values

In a base transceiver station in a cellular network, a digital signal processor generates a baseband input signal, which is converted to analog and transmitted by a transmitter at radio frequency. In accordance with the present invention, the baseband input signal is scaled by a selected factor from a predetermined table of scaling factors. The scaling factors are determined based on measured output power characteristics of the transmitter and provide frequency compensation caused by filtering ripple and/or attenuation compensation caused by uncertainties in internal attenuators.

Method and apparatus that compensates for output power variations in a

A transmitter in a base transceiver station in a wireless telephony network uses a direct up-conversion scheme to convert an input signal with in-phase and quadrature phase (I, Q) components to a radio frequency within a transmit band. A low-pass filter filters noise from the input signal components and a phase equalizer equalizes the phase distortions caused by the filtering in the input signal components. The signal components are then provided to an up-converter, such as a quadrature modulator, for conversion to a radio frequency signal within a transmit band. The transmitter of the present invention complies with the TIA'S 15-54 emission requirements.r connected to the first low pass filter and a second phase equalizer connected to the second low pass filter.

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San Diego, CA, United States of America

Hassan Zamat