Abstract: A integrated circuit card having a rigidized frame to surround the electronic devices on a printed circuit (PC) board. The card includes a frame and integral cover for the top and bottom. The top and bottom are constructed out of a material that does not interfere with the use of an antenna coupled to the board assembly within the card. The bottom and top are coupled together using pins. When the two are coupled together the frame is better supported.

Abstract: A novel direct conversion receiver utilizing a sample and hold circuit for subsampling the input signal. The output of the sample and hold circuit is applied to a sigma-delta loop to provide a high speed low resolution data stream which in turn is applied to a decimator which provides a high precision, low data rate signal having quadrature outputs.

Abstract: An apparatus and method to transmit and receive digital signals in a communication system having a power source that provides power to a portion of a communication device and a mechanism to disable power to that portion of the communication device for periods of time, such that a reduced power consumption state is entered. Also included is sampling hardware to sample the signal during those periods of time when the communication device is not in the reduced power consumption state, which occurs when data is transferred or received.

Abstract: A low noise narrow band amplifier with low power consumption for amplifying radio frequency and microwave signals. The amplifier includes a high frequency transistor that has a cut-off frequency greater than the center frequency of the input signal. The amplifier includes an emitter inductor for low noise and better input match. The amplifier is stabilized for out-of-band high frequency oscillations by a collector inductor and a base inductor. The amplifier is further stabilized unconditionally for out-of-band high frequency oscillations by a stabilizing circuit coupled between the output and ground, including a stabilizing capacitor in series with a stabilizing resistor.

Abstract: Improved integration and simplified construction of direct conversion receivers is achieved by providing selectivity in the early stages of a sigma delta converter to reject adjacent channel signals and thereby allow greater dynamic range for the desired input signals. A bandpass sigma delta converter is taught which is suitable for use with signals having multiple protocols. In a first stage, an aliased input signal is applied to two filters having desired and preferably programmable filter characteristics which provide selectivity to the input signal. A third filter is utilized having a programmable center frequency, which receives as an input signal the sum of the filtered input signal plus the quantization noise of the first stage. This provides a first intermediate output signal of desired selectivity.