Abstract: A bias cell for use in biasing all NMOS differential pair is configured to substantially eliminate variations in transconductance caused by body effects. In one example, a voltage threshold mismatch between NMOS devices of the bias cell is substantially eliminated to thereby reduce variations in transconductance caused by body effects. To reduce the voltage threshold mismatch, the bias cell includes a transconductance-setting resistor connected between gates of a pair of current source devices. Circuitry is connected to the resistor for applying a voltage across the resistor. A bias line connects a signal output from the bias circuit to the differential pair.

Abstract: A system and method for deciding whether to initiate an idle handoff in a wireless communications system is disclosed. A mobile station having an integrated chip and software instructions executed by that chip obtain samples at first and second times of the pilot signals radiated by first and second base stations. A determination is then made whether to initiate an idle handoff based upon a comparison of the total strengths of the second time samples and a position-weighting term with a design constant. The position-weighting term accounts for the change in position of the mobile station relative to the first and second base stations in between the first and second sample times. The position-weighting term may itself be weighted to account for the strength of the earliest arriving multipath component of the first and second pilots relative to the total strength of the first and second pilots.

Abstract: A wireless communication device provides streamlined access to recording functions that allow a user to readily record information from a called directory information service provider or other predetermined number. Directory service provider numbers and other predetermined numbers are stored in the system and compared with a user selected destination telephone number. If a match is detected, the system display automatically enables a recording function or prompts the user to manually activate the recording function to permit the user to manually record information obtained from the directory information service provider. Alternatively, the information may be automatically transferred directly into the system without user intervention through a communication link using a formatted data exchange. The system includes options for editing the recorded information, permanently storing the recorded information, and completing a call to the telephone number provided by the service.

Abstract: A method for conveying packet data from a CDMA mobile station to a GSM network, including communicating with a GSM service node to establish a data link from the mobile station to the network via a radio communications base station. The packet data are conveyed between the mobile station and the base station over a CDMA air interface and are then transferred over the link between the base station and the network.

Abstract: A system for providing immediate access to detailed information about a wireless call. The system includes a first mechanism for placing a wireless call. A second mechanism times the call to provide a call duration value. A third mechanism computes the detailed information from the call duration value and a predetermined value associated with the call. A fourth mechanism displays the detailed information. In a specific embodiment, the predetermine value is a billing rate associated with the call and the detailed information is expense information. The third mechanism includes a computer that runs software for computing the detailed information from the call duration value and the billing rate. The software includes a routine that detects when the wireless phone is being used for a call and times the call. The software also includes a mechanism for providing user-selectable parameters for controlling the third mechanism.

Abstract: A subscriber unit that supports more than one voice service option and selects the appropriate voice service option when originating and receiving a call. The subscriber unit includes a memory to store parameter values, including a first voice service option parameter value and a second voice service option parameter value. The subscriber unit also includes a means for determining whether the subscriber unit is within a home system or is roaming, and a selecting means for selecting from among at least a first voice service option corresponding to the first voice service option parameter value and a second voice service option corresponding to the second voice service option parameter value. The selecting means selects the first voice service option if the subscriber unit is within the home system, and selects the second voice service option if the subscriber is roaming.

Abstract: Microprocessor resource utilization by a searching process are controlled by determining a search window size, accessing a lookup table to determine an integration interval and a number of non-coherent passes, and commanding a searching process to execute a multipath search according to these parameters. The lookup table comprises a plurality of integration intervals and corresponding number of non-coherent passes indexed according to search window such that an execution duration of the search process remains nominally constant over a variety of search window sizes.

Abstract: A hardware-efficient transceiver. The transceiver includes a digital circuit for converting baseband signals to intermediate frequency signals. A signal source provides a first periodic signal of a first frequency. A direct digital synthesizer provides a second periodic signal of a second frequency from the first periodic reference signal. An upconverter circuit digitally upconverts the baseband signals to digital intermediate frequency signals using the second periodic signal A digital-to-analog converter converts the digital intermediate frequency signals to analog intermediate frequency signals using the first periodic signal. In the transceiver implementation, the digital circuit upconverts a first transmit signal from a first frequency to a second frequency in response to the second periodic signal and provides a digital transmit signal in response thereto. A second circuit is provided for converting the digital transmit signal to an analog transmit signal.

Abstract: A system for facilitating handoff adapted for use with a telecommunications network. The system includes position equipment for determining the location of a mobile transceiver within a region containing a first cell and a second cell. A comparison circuit compares the location with a predetermined handoff area within the region and provides a control signal in response thereto. A handoff initiation circuit initiates handoff of the mobile transceiver between the first cell and the second cell in response to the control signal. In a specific embodiment, the handoff is a hard handoff. The position equipment includes Global Positioning System (GPS) equipment including a mobile unit GPS receiver and signal interface. The comparison circuit includes a positional database that stores latitudinal and longitudinal information corresponding to the predetermined handoff area. The comparison circuit also includes a Code Division Multiple Access selector.

Abstract: A novel and improved method and apparatus for address generation in an interleaver is provided. In accordance with one embodiment of the invention, an address is generated using a random address fragment and a bit reversed address fragment. The bit reversed address fragment is selected by first generating two consecutive candidate bit reversed fragments. The second bit reversed address fragment is selected when the first bit reversed address fragment generates an address that is greater than a maximum address. The address generator allows address generation for interleaver and deinterleaver frame sizes of N, where N is not an integer power of two, without any cycle penalty.

Abstract: A method and apparatus for RF amplification of a transmit signal within a wireless phone. The amplifier chain is composed of three parts, a pre-driver, a bypassable driver amp, and a power amp. The configuration of the amplifier chain is adjusted in real time to optimize power consumption for a given output power requirement. At low output power levels the driver amp is bypassed and the power amp is provided a low bias current. At medium output power levels the driver amp is bypassed and the power amp is biased at a moderate current. When high output power is required the driver amp is utilized and the power amp is provided a high bias current. The driver amp is shut down when in the bypassed state. The result of implementing this amplifier configuration is an increase in the efficiency of the transmit amplifier. The increase in amplifier efficiency results in increased talk times for battery powered wireless phones.

Abstract: A method and apparatus for remote control of software and hardware features of a wireless communication device using Short Message Services (SMS). A wireless communication device with SMS capabilities can be remotely configured by sending specifically configured SMS messages. A manufacturer can configure a wireless device to have control over certain features accessible through SMS messages. A configuring SMS message is constructed using a specific format to inform the wireless device of the presence of a feature control message. Predetermined combinations of characters unlikely to occur in normal messages are used as message start and stop delimiters. A series of fields are defined in the SMS message with the fields separated by delimiters distinct from the message start and stop delimiters. Commands may be sent to the wireless device using point-to-point as well as broadcast SMS messages.

Abstract: An interface circuit for converting a digital signal to an analog signal. The interface circuit includes a time response adjustment circuit, a modulator, and a filter. The time response adjustment circuit receives the digital signal and generates an adjusted signal. The modulator couples to the time response adjustment circuit, receives the adjusted signal, and generates a modulator signal. The filter couples to the modulator, receives the modulator signal, and generates the analog signal. The analog signal has a time response that is modified by the time response adjustment circuit. In an embodiment, the time response adjustment circuit includes a gain element, a delay element, and a summer. The gain element receives and scales the digital signal by a scaling factor. The delay element receives and delays the digital signal by a time delay.

Abstract: A method and apparatus for scheduling the paging wake-up time in a wireless mobile station. The decision to wake-up a mobile station in order to decode a slotted paging message is determined probabilistically. An initial missed page rate constant, M, is loaded within the mobile station. A measurement of the particular mobile station paging rate, R, is made over a time period T. The measured paging rate R is compared to the initial missed page rate constant M. If the missed page rate M is greater than the measured paging rate R the mobile station does not respond to the next paging slot. If the missed page rate M is less than the measured paging rate R a number based on the ratio of M to R is used as an input to a uniform random number generator. The output of the uniform random number generator determines whether or not to wake-up during the next paging slot. The measured paging rate R is updated as a running average.

Abstract: A technique for parsing numbers on a display in a wireless communication device utilizes a data storage area containing data related to the dialing plan for the particular location of the user, such as a country. A parser receives the number and applies the number digit by digit to the data in the dialing plan storage area to determine whether the number corresponds to a known telephone number format for the particular country. If the number corresponds to a known format, one of a predetermined number of parsing formatting characters are applied to the number and the number with formatting characters is shown on a display. The user may edit the formatting characters to customize the format for personal preferences. The number may be provided to the parser by manual entry of digits by the user via a keypad, or may be automatically provided to the parser by user selection of a number in a telephone book storage area, a call history storage area, or the like.

Abstract: In a system for mobile wireless communication, it is desirable to minimize the period of time during which the RF circuitry is powered (i.e. the RF power period). A novel method and apparatus for pilot monitoring during standby mode defers processing of pilot search results until the RF power period has passed. This approach allows more searches to be performed without extending the RF power period, thus improving idle handoff performance without reducing battery charge life.

Abstract: A method and apparatus for adaptively correcting D.C. offset errors imposed upon signals in a communication device. The present invention includes a feedback loop correction circuit and method for measuring and reducing D.C. offset errors imposed upon analog transmission signals by transmit digital-to-analog converters (DACs) and associated analog reconstruction filters. A digital feedback loop is used to remove the D.C. offset errors from the analog transmission signals prior to transmission. In the preferred embodiment, the digital feedback loop includes a pair of analog-to-digital converters, a digital D.C. offset correction circuit, and a pair of adders. The transmission signals are digitized, filtered, and digitally processed by the correction circuit to generate offset correction signals that are equal to the undesired D.C. offset error present in the transmission signals. The correction signals are added to the digital input baseband signals thereby removing the undesirable D.C.

Abstract: A power amplifier circuit arrangement particularly useful for portable phones used in wireless systems. A power amplifier stage can be partially or completely bypassed so that multi-stage amplifiers can be built that allow wide dynamic range of power amplification to be obtained efficiently. A switch at the input of an amplifier stage couples an input signal either to an amplifier or to a bypass path. The output of the amplifier is coupled to a first impedance-transforming network. The bypass path includes a second impedance-transforming network. A third impedance transforming network couples the outputs of the first and second impedance transforming networks. The impedance transforming networks are constructed and arranged so that input and output signals see the correct load regardless of whether the amplifier is used or bypassed. Using the principles of this invention, multi-stage amplifiers can be constructed including input and bypass attenuators to achieve a wide range of gain levels.

Abstract: A serial Viterbi decoder having a chainback cache is provided for use in a mobile telephone. In one embodiment described herein, the decoder includes a branch error metric block, an add-compare-select unit, and a chainback block including a chainback RAM, a full chainback cache and chainback controller circuitry. The chainback cache caches decision bits from previous process cycles such that full chainback operations need not always be performed. The chainback cache is configured to cache on all reads. With the chainback cache, significant savings in power consumption and processing time may be achieved with only a relatively modest increase in the amount of circuitry required. In another embodiment, a full chainback cache is not provided. Rather, the chainback block instead includes an L+1 bit RAM, an updown counter and a shift register configured to emulate a chainback cache.