Abstract: A transceiver (10) includes a transmitter (16) that receives a digital data stream from a digital signal processor (18) to delay lines (20, 30). The delay lines (20, 30) provide an address to a ROM look-up table (40). Another input of the look-up table (40) receives a signal that selects protocols such as TDMA, CDMA, and GSM. A multi-accumulator fractional-N synthesizer (48) receives phase derivative coefficients and a DAC (46) receives amplitude modulation coefficients from the look-up table (40) based on the selected protocol. The analog output signals from the DAC (46) and the synthesizer (48) are received by a variable gain amplifier (54) that generates an RF amplitude and frequency modulated output signal for transmission from the transmitter (16).

Abstract: A transceiver (10) includes a transmitter (16) that receives a digital data stream from a digital signal processor (18) to delay lines (20, 30). The delay lines (20,30) provide an address to a ROM look-up table (40). Another input of the look-up table (40) receives a signal that selects protocols such as TDMA, CDMA, and GSM. A multi-accumulator fractional-N synthesizer (48) receives phase derivative coefficients and a DAC (46) receives amplitude modulation coefficients from the look-up table (40) based on the selected protocol. The analog output signals from the DAC (46) and the synthesizer (48) are received by a variable gain amplifier (54) that generates an RF amplitude and frequency modulated output signal for transmission from the transmitter (16). The look-up table (40) stores phase derivative coefficients and amplitude modulation coefficients that correct for non-linearity in the variable gain amplifier (54).

Abstract: A cordless telephone has receive (12) and transmit (14) signal paths for passing voice signals. Sidetones normally appear in the receive signal path from the near party's voice. A signal strength comparator (34) monitors the transmit signal path and the receive signal path and asserts a gain control signal when the transmit path signal strength exceeds a threshold set to a predetermined value below the receive path signal strength. The gain control signal decreases the gain (42) in the receive signal path to reduce undesirably loud sidetones in the speaker earpiece. When the transmit path signal strength is less than the predetermined threshold, the gain control signal is not asserted allowing maximum amplification in the receive signal path as the sidetone is sufficiently small as to not interfere with the main received voice signal, or otherwise become noticeably loud in the speaker earpiece.

Abstract: A motion sensing apparatus comprises two substrates, contact means, and at least one electrically conductive element. A first substrate contains an electrically conductive layer disposed on one of its major surfaces. A second substrate contains a hole, including an interior surface that extends from one major surface to another, such that a cavity is formed by the planes of the major surfaces and the interior surface. The second substrate is positioned substantially parallel to the first substrate, such that the electrically conductive layer is positioned within an area defined by the hole. The contact means and the electrically conductive element are placed within the cavity, such that a motion sensing signal is produced when the electrically conductive element comes in contact with both the contact means and the electrically conductive layer.