Abstract: A communication device (100) and method therefore for compensating an oscillator (146). The communication device (100) includes a receiver (110) for receiving message information transmitted on a predetermined channel (105), an oscillator (146) having a frequency of operation set by a controller (116) for enabling reception of the message information on the predetermined channel (105), and a decoder (114) for decoding the message information received, and for deriving there from messages and channel quality information. The controller (116) is responsive to the messages derived, for storing the same, and further responsive to the channel quality information derived for generating a compensation signal when the value of the channel quality information exceeds a predetermined value. The compensation signal that is generated by the controller (116) effects shifting of the frequency of operation of the oscillator (146) to center reception of the communication device (100) on the predetermined channel (105).

Abstract: An automatic gain control (AGC) system (100) for a controlled gain receiver (1101) includes a magnitude generator (160) and a gain corrector (170). The magnitude generator (160) generates a binary voltage squared signal (165) having a binary value that is directly proportional to a recovered signal power of an intercepted signal (113). The gain corrector (170) determines an adjustment of a gain control value (195) as a multiple of increments that are approximately 3 decibel (dB), by shifting (475, 445) a reference threshold by one or more bits and comparing (485, 455) the shifted reference threshold to the binary voltage squared signal. An initial setting of a state of a step attenuator (114) during a track mode (172) is determined during a warm up mode (171) by comparing the binary voltage squared signal (165) to two different thresholds (245, 255).

Abstract: A speakerphone accessory (100) is provided for use with a portable telephone (102). The speakerphone accessory (100) has a high-level speaker assembly (222) that includes a transducer (500) coupled to first and second resonators (502, 504). The first and second resonators (502, 504) are designed so that the first resonator (502) is most efficient at a high frequency while the second resonator (504) has maximum response at a low frequency. The frequency ranges produced by the first and second resonators (502, 504) overlap to reproduce frequencies between the high and low frequencies. The high-level speaker assembly (222), therefore, provides an acoustic bandpass having improved response when compared to the response of the transducer (500) alone.

Abstract: A portable radio communication device (303) includes power control circuitry (315) for monitoring the voltage level incoming from a battery (317), and provides power to the rest of the radio communication device (303). The power control circuitry (315) includes a boost regulator (407) that is used to generate an internal reference signal for use throughout the radio communication device including an analog to digital converter (ADC) for digitizing the battery voltage for use by the power control circuitry (315). The power control circuitry (315) compares the digitized battery voltage to thresholds to control power to the remainder of the radio communication device (303). Additionally, a secondary comparator (413) is provided to prevent damage to the battery and radio communication device circuitry. The secondary comparator uses multiple undervoltage thresholds depending upon the power state of the radio communication device (303).

Abstract: A method and apparatus for processing embedded messages at a mobile station including a subscriber identity module (SIM) identifying the subscriber, for example, a GSM or a non-GSM wireless telephone. The process includes receiving a message having a protocol identifier, transferring at least a portion of the message to the subscriber identity module if the protocol identifier satisfied a condition, extracting information from the at least portion to of the message at the subscriber identity module if a protocol identified by the protocol identifier is supported by the subscriber identity module.

Abstract: Battery life and cooling are improved in an electronic device. A thermoelectric module and phase change material module are placed near a heat source in an electronic device. The thermoelectric module and phase change material module insulate a surface to be cooled on the electronic device. The thermoelectric module generates an electrical current in response to a temperature differential at opposite surfaces on the thermoelectric module. The phase change material module enhances or limits the temperature differential seen at the thermoelectric module. The electrical current generated by the thermoelectric module is used to charge a battery of the electronic device.

Abstract: By time-sharing demodulator hardware between a primary data path (165), a power control data path (161), and a received signal strength indicator (RSSI) path (163), an entire power control data path (161) can be implemented in a demodulator (140) of a spread spectrum subscriber unit receiver with a low increase in gate count. The primary data path (165) and the power control data path (161) time-share a complex conjugate generator (270), a complex multiplier (280), and a real component extractor (290). Due to timing requirements, though, the channel estimation filter (240) of the primary data path cannot be time-shared with the power control data path. Instead, dynamic coefficient scaling is added to an infinite-duration impulse response (IIR) filter in the RSSI path (163) so that the IIR filter (250) with dynamic coefficient scaling can be time-shared between the RSSI path (163) and the power control data path (161).

Abstract: An exciter matching circuit (125), interstage matching circuit (134), and harmonic filter matching circuit (140) match impedances at the input to a two-stage power amplifier (130), between the first stage (132) and the second stage (136) of the power amplifier (130), and at the output of the power amplifier (130) for more than one frequency band of interest. In a GSM/DCS dual band radiotelephone (101), the matching circuits (124, 134, 140) provide low return loss at 900 MHz when the dual band transmitter (110) is operating in the GSM mode. The harmonic filter matching circuit (140) also filters out signals at 1800 MHz, 2700 MHz, and high order harmonics. When the dual band transmitter (110) is in DCS mode, however, the matching circuits (124, 134, 140) provide a low return loss at 1800 MHz and filter out signals at 2700 MHz and harmonics of 1800 MHz.

Abstract: An exciter matching circuit (125), interstage matching circuit (134), and harmonic filter matching circuit (140) match impedances at the input to a two-stage power amplifier (130), between the first stage (132) and the second stage (136) of the power amplifier (130), and at the output of the power amplifier (130) for more than one frequency band of interest. In a GSM/DCS dual band radiotelephone (101), the matching circuits (124, 134, 140) provide low return loss at 900 MHz when the dual band transmitter (110) is operating in the GSM mode. The harmonic filter matching circuit (140) also filters out signals at 1800 MHz, 2700 MHz, and high order harmonics. When the dual band transmitter (110) is in DCS mode, however, the matching circuits (124, 134, 140) provide a low return loss at 1800 MHz and filter out signals at 2700 MHz and harmonics of 1800 MHz.

Abstract: An exciter matching circuit (125), interstage matching circuit (134), and harmonic filter matching circuit (140) match impedances at the input to a two-stage power amplifier (130), between the first stage (132) and the second stage (136) of the power amplifier (130), and at the output of the power amplifier (130) for more than one frequency band of interest. In a GSM/DCS dual band radiotelephone (101), the matching circuits (124, 134, 140) provide low return loss at 900 MHz when the dual band transmitter (110) is operating in the GSM mode. The harmonic filter matching circuit (140) also filters out signals at 1800 MHz, 2700 MHz, and high order harmonics. When the dual band transmitter (110) is in DCS mode, however, the matching circuits (124, 134, 140) provide a low return loss at 1800 MHz and filter out signals at 2700 MHz and harmonics of 1800 MHz.

Abstract: An apparatus and method enables elements of a phase locked loop (PLL) (300). The PLL 300 includes a plurality of elements (202, 203, 204, 205). Each element produces an output signal (207, 208, 209, 116 or 117). Each element has a response time (t3−t2) defined by the difference in time between a first time (t2) at which the element is enabled and a second time (t3), occurring after the first time (t2), at which the output signal of the element reaches a steady state condition. A voltage controlled oscillator (204) of the plurality of elements, having a first response time (t3−t2) is enabled at the first time (t2) responsive to a first control signal (302). A loop divider (205) of the plurality of elements, having a second response time less than the first response time (t3−t2), is enabled responsive to the first response time (t3−t2) and a second control signal (303). The present invention advantageously provides fast lock time for the PLL (300).

Abstract: A difference drive diversity antenna structure (200) and method for a portable wireless communication device (230) aligns a first linear antenna (240) parallel to a major axis (245) of the communication device and drives dual radiators (252, 254) of a second antenna (250) at equal magnitudes but with a 180 degree phase difference. A difference drive diversity antenna structure implemented in a portable wireless communication device maintains significant decorrelation between the first antenna (240) and the second antenna (250) over the common frequency ranges of the dual radiators (252, 254). Also, antenna currents on the body of the communication device are minimized and the effects of a hand or body near the communication device are reduced.

Abstract: A radiotelephone (101) is adapted to generate a plurality of distinctive vibrating alert patterns. An antenna (201) receives radio frequency (RF) signals including an incoming telephone call signal (121). A receiver (205), operably coupled to the antenna (201), receives the incoming telephone call signal (121). A vibrating alert generator (223) generates a vibrating alert pattern when enabled. A controller (215), operably coupled to the receiver (205) and the vibrating alert generator (223), enables the vibrating alert generator (223) to generate the vibrating alert pattern (301) as one of a plurality of distinctive vibrating alert patterns (301-312) when the incoming telephone call signal (121) is received. The present invention advantageously permits the user or the radiotelephone system (100) to select a preferred distinctive vibrating alert pattern (301), or to assign a particular distinctive vibrating alert pattern (301) to a particular incoming telephone call signal (121).

Abstract: A wireless communication device (10) is provided for maintaining acceptable acoustic coupling, increasing display and data input device capability and increasing antenna performance to encourage further miniaturization and weight reduction thereof. Two moveable housing portions (12) and (14) are moveable between a closed (18) and an open (20) housing position and matively engage to provide an expandable housing while aligning earpiece (26) and microphone (28) transducers on a center axis (30) of the device (10). Paging and radiotelephone functions of the device are configured responsive to the position of the housing portion (12). The radiotelephone (10) allows communication in both a private mode and a hands-free mode, which enables a user to answer a call without opening the radiotelephone (10).

Abstract: A wireless communication device (10) is provided for maintaining acceptable acoustic coupling, increasing display and data input device capability and increasing antenna performance to encourage further miniaturization and weight reduction thereof. Two moveable housing portions (12) and (14) are moveable between a closed (18) and an open (20) housing position and matively engage to provide an expandable housing while aligning earpiece (26) and microphone (28) transducers on a center axis (30) of the device (10). Paging and radiotelephone functions of the device are configured responsive to the position of the housing portion (12). The housing portion has a lens for viewing a display (46) thereunder and keycaps for actuating a keypad (54) thereunder when the housing portion (12) is in the closed housing position (18). An antenna (56) is extendable beyond the moveable housing portion (12).

Abstract: The pulse-shaping look-up table with transient suppression (530) avoids hard turn-on and turn-off transients by modifying word segments of initial and final digital words during transmission of a digital data sequence. A controller (570) sends a mode signal and a digital data sequence to the pulse-shaping look-up table with transient suppression (530). A mode buffer and command block (560) uses the mode signal to control the creation of initial and final digital words created by a data buffer and control block (550) from the digital data sequence. The digital words are used by a look-up table (540) to create a sampled digital output waveform sequence. The pulse-shaping look-up table with transient suppression (530) provides an accurate output waveform sequence with reduced spectral emissions even during start-up and shut-down of digital data transmissions.

Abstract: An off-channel leakage power monitor implemented in a transceiver (100) dynamically measures adjacent and alternate channel leakage power produced by nonlinearities in a transmitter (110) power amplifier (116). A main local oscillator (124), offset voltage-controlled oscillator (122), and second local oscillator (170) are adjusted to obtain on-channel power, adjacent channel power, and alternate channel power measurements using a measurement calculator (185) implemented in a digital signal processor (180) or as a gate array in a receiver (140). Once the off-channel leakage power measurements have been obtained, any number of techniques can be used to extract increased efficiency from the power amplifier (116) while maintaining acceptable linearity under changing operating conditions.

Abstract: An exciter matching circuit (125), interstage matching circuit (134), and harmonic filter matching circuit (140) match impedances at the input to a two-stage power amplifier (130), between the first stage (132) and the second stage (136) of the power amplifier (130), and at the output of the power amplifier (130) for more than one frequency band of interest. In a GSM/DCS dual band radiotelephone (101), the matching circuits (124, 134, 140) provide low return loss at 900 MHz when the dual band transmitter (110) is operating in the GSM mode. The harmonic filter matching circuit (140) also filters out signals at 1800 MHz, 2700 MHz, and high order harmonics. When the dual band transmitter (110) is in DCS mode, however, the matching circuits (124, 134, 140) provide a low return loss at 1800 MHz and filter out signals at 2700 MHz and harmonics of 1800 MHz.