Abstract: Speech presence is detected by first bandpass filtering (141, 143, 145) the speech to split it into banks of sub-bands. A matrix of shift registers (150) store each sub-band of speech. A power determining circuit (259) then determines individual power measurements of the speech stored in each shift register element. A variance combining circuit (160) combines the individual power measurements to provide a variance for the individual shift registers. A comparator circuit (170) finally compares the variance with at least one threshold to indicate whether speech is detected.

Abstract: In a radiotelephone (30), a channel estimator (39) receives a time division multiple access (TDMA) information signal (31) including a synchronous codeword (44), formed of a first subset of seven sequential symbols (47) followed by a second subset of seven sequential symbols (48), followed by a data sequence (45) formed of multiple sequential symbols. The channel estimator (39) uses the first subset (47) to train, via initializing (51) and updating (52), the channel estimator to stabilize the channel estimate. The channel estimator (39) uses the second subset (48) to train, via initializing (53) and updating (54), the predictor to improve the future accuracy of the channel estimate. The channel estimator (39) then tracks (55) the channel estimate over the data sequence (45) by updating the channel estimator and the predictor over the data sequence (45), without substantially affecting the stability of the channel estimate or the future accuracy of the channel estimate.

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: The partially-parallel trellis decoder with equalizer (360) uses multiple channel estimators (377, 379) but less than one independent channel estimator for each state. The state information set from the state with the best state metric as computed during the previous time period is used to update a primary channel estimator (377), and a state information set from the state with the second best state metric as computed during the previous time period is used to update a secondary channel estimator (379). Each updated channel estimator (377, 379) processes the corresponding state information set to calculate the possible transmitted symbols and their associated state metrics. Because there are fewer channel estimators than states, any unassigned states are processed using the primary channel estimator (377) but do not update the primary channel estimator (377).

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 as (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: A flowchart (400) includes the step (402) of collecting a predetermined number of TOA measurements arriving at the assisted satellite positioning mobile station from a base station, the step of (406) simultaneously collecting a corresponding number of GPS position measurements of a position of the GPS receiver, and the step (410) of computing the base station location and/or the step (414) of computing a perceived time bias offset required for a message to travel between the base station and the mobile station using the predetermined number of TOA measurements and the predetermined number of GPS position measurements.

Abstract: An assisted global positioning satellite (Assisted GPS) system has a GPS reference network node (260) that collects GPS satellite broadcast messages and prepares separate GPS assistance messages to be modulated by a base transceiver station (BTS) (202) on a cellular carrier signal (201) and sent to single or multiple handset (204). In a first preferred embodiment, instead of the handset (204) receiving standard ephemeris and clock correction data elements in a GPS assistance message, a compressed GPS assistance message containing XYZ information contains a GPS satellite's coordinate position modified according to the satellite clock correction. In a second preferred embodiment, there is a first type of compressed GPS assistance message containing subframe 1, 2, 3 data of a GPS satellite broadcast message and a second type of compressed GPS assistance message containing subframe 4, 5 data of a GPS satellite broadcast message.

Abstract: When an input digital signal, having a portion with an associated control value, is connected to a digital filter with adaptive compensation, the digital filter with adaptive compensation selects one of a plurality of coefficient scalers (9501, 9601) as directed by a control bus (990). As the input digital signal propagates through the filter, one of a plurality of next coefficient scalers (9502,9602) are selected by the control bus (990). The digital filter with adaptive compensation interleaves in time the coefficients of multiple conventional filters in order to filter each portion of the digital signal according to its associated control value.

Abstract: A variable gain control circuit (125, 127) includes a programmable operational transconductance amplifier (OTA) circuit (214) and a programmable conveying circuit (544). The conveying circuit (544) has a programmable differential circuit (550) interconnected to a pair of programming inputs (564, 566). The pair of programming inputs (564, 566) is interconnected to a pair of programming inputs (238, 240) that set the gain of the OTA circuit (214). When the OTA circuit (214) is configured as an operational transconductance filter (112, 113), the programmable differential circuit (550) can adjust the gain of the conveying circuit (544) to compensate for changes in the input impedance of the filter (112, 113). The programming inputs (238, 240) that set the input impedance and bandwidth of the filter (113, 113) also control the amount of signal current transmitted by the conveying circuit (544).

Abstract: The hang-up cup assembly (100) for a radiotelephone has a cradle (200) secured to a pedestal (300) using a ball (320) and a socket (220) of a ball-and-socket joint (120), a screw (400), and a dome nut (600). The ball-and-socket joint (120) is compressed by the screw (400) and the dome nut (600) to retain the hang-up cup assembly (100) in the desired position. The hang-up cup assembly (100) has a low profile, is easy to install, and can be adjusted by an end user by slightly loosing the easily-accessible screw (400), repositioning the cradle (200) relative to the pedestal (300), and tightening the screw (400) to compress the ball-and-socket joint (120) and maintain the desired new position.

Abstract: A transient-suppressing mode switch (100) uses a state machine (120) in conjunction with a soft switch (114) to control a first mode signal sent from a first mode signal source (112) to a first soft switch input and a second mode signal from a second mode signal source (130) to a second soft switch input. When switching from a first mode to a second mode, the state machine delays the transition of the second mode signal from a constant zero value to a non-zero value until after the amplitude of the first mode signal at the first soft switch input has decayed to a sufficiently small value in order to reduce transients caused by switching.

Abstract: A watch radiotelephone (10) comprises a watch face (12) and a keypad (14). The watch face (12) indicates a time of day in an analog format. The analog format includes twelve indicia (32-43) positioned around a perimeter (30) of the watch face (12). The twelve indicia (32-43) represent and correspond to twelve hours in a day in the analog format. The keypad (14) includes twelve keys (46-57). Individual keys (46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57) of the twelve keys (46-57) are positioned to correspond with individual (32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43) of the twelve indicia (32-43). A user of the watch radiotelephone (10) is permitted to actuate a predetermined number of the twelve keys (46-58) of the keypad (14) in a predetermined sequence to enter a telephone number in accordance with a user's familiarity of the twelve indicia (32-43) located around the perimeter (30) of the watch face (12). A timekeeping circuit (118) provides the time of day to the watch face (12).

Abstract: A method and apparatus for determining time in a GPS receiver is provided according to the invention. The method includes the steps of capturing (304) GPS data in a GPS message for a predetermined period of time, locating (308) a predetermined data sequence in the captured data, and determining (311) a time offset between a data capture start time and a time of arrival of the expected data pattern.

Abstract: The channel scanning method and apparatus uses a priority table (500) to determine the action that should be taken by a mobile station (MS) during an idle frame of a traffic channel (TCH) in order to decode the base station identification code (BSIC) of each channel in a reporting table every ten seconds in accordance with GSM specification 05.08. The priority table (500) has channel groups (510, 520, 530, 540, 550, 560) based on the role of the cell relative to the MS, the time elapsed since the cell's broadcast channel (BCH) was most recently synchronized, the expected amount of time needed to either detect a frequency burst (FCH) or demodulate a synchronization burst (SCH), the power level of a BCH, and the detected noise level. The priority table is used by a scheduler (600) to aid the MS in efficiently using each idle frame and reducing nonuse of idle frames.

Abstract: A display module (100) with reduced power consumption uses a control circuit (110) to reset row and column display drivers (130, 140) and turn off a portion of the display (150) when the display module (100) is in a partial display mode. The partial display mode allows a reduction in the driving voltages for the display which in turn reduces the power needed by the bias voltage divider (120) which produces the driving voltages. The display module (100) with reduced power consumption is applicable to both LCD and non-LCD technologies, such as electroluminescence or cathode ray tube, using a multiplex or scanning methodology.

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: Prior to placing a call, a receiver (24) in a radio (10) receives a phone number transmitted by a calling party to produce a received phone number (38). The received phone number (38) is stored in a memory unit (16) of the radio (10). Numeric digits forming a prefix number (40) are inserted before the received phone number (38) in the memory unit (16) responsive to a number of digits in the received phone number (38) to produce an edited phone number (39). A transmitter (20) in the radio (10) transmits the edited phone number (39) to place the call to the received phone number (38). This method for editing a received phone number (38) prior to placing a call to the received phone number (38) advantageously simplifies the dialing process when placing the call to the received phone number (38).