Abstract: A radio-frequency receiver includes built-in-self-test (BIST) circuitry which generates a self-test signal. A local oscillator signal is divided. A self-test oscillation signal is generated, based, at least in part, on the frequency-divided local oscillation signal. The self-test signal is generated based on the self-test oscillation signal. The BIST circuitry includes a divider, which divides the self-test oscillation signal. The frequency-divided local oscillation signal and the divided self-test oscillation signal are used to perform one or more of generating the self-test oscillation signal and controlling the generation of the self-test oscillation signal. The radio-frequency receiver may be an automotive radar receiver.

Abstract: Techniques for controlling a low-profile medium wave transmitting system are provided. An example of an antenna system according to the disclosure includes a first radiator operably coupled to a first amplifier, a first modulator operably coupled to the first amplifier and configured to provide a first radio frequency signal to the first amplifier, a second radiator operably coupled to a second amplifier, a second modulator operably coupled to the second amplifier and configured to provide a second radio frequency signal to the second amplifier, a control module operably coupled to the first modulator, first amplifier, the second modulator, and the second amplifier, the control module being configured to control a delta phase value based on the first radio frequency signal and the second radio frequency signal, and control the power output of the first amplifier and the second amplifier.

Abstract: A device may comprise: a storage for storing a reference output representing an output of an electrical circuit at a reference temperature; one or more processors, configured to: determine a temperature shift based on a comparison of an output of the electrical circuit sensed at a sensing temperature and the reference output; determine a plurality of coefficients of a model of the temperature shift, wherein the model implements one or more functions that associate the plurality of coefficients and a temperature with the temperature shift at the temperature.

Abstract: A wearable radio frequency receiver device is provided, which includes a receiver antenna configured to receive an interrogation signal from a transmitter. The receiver device further includes a sensor coupled to the receiver antenna and configured to receive a physiological input from a user wearing the device and generate a sensor signal based on the physiological input, and a modulator configured to perform direct modulation on the received interrogation signal based on the sensor signal to encode the physiological input in the directly modulated interrogation signal. The receiver antenna may be configured to reflect at least a portion of the directly modulated interrogation signal as backscatter radiation. A transceiver including a transceiver antenna may be provided to receive the directly modulated interrogation signal, and the modulation receiver may be configured to process the directly modulated interrogation signal and output a decoded physiological input.

Abstract: A communication device (device) includes a communication interface and a processor, among other possible circuitries, components, elements, etc. to support communications with other device(s) and to generate and process signals for such communications. The device receives a ranging instruction signal, which includes an initial power and at least one power step, from another device. The device processes the ranging instruction generates a first ranging signal based on the initial power. The device then transmits the first ranging signal to the another device. When a ranging response to the first ranging signal is received from the another device, the device determines that the device is successfully ranged to the another device. Alternatively, when no ranging response is received, the device generates a second ranging signal based on the initial power and the at least one power step and transmit the second ranging signal to the another device.

Abstract: Systems and methods related to time and frequency synchronization of a base station in a cellular communications network are disclosed. In some embodiments, a method of operation of a synchronizing base station comprises selecting a first base station for frequency synchronization and a second base station for time synchronization, where the second base station can be different than the first base station selected for frequency synchronization. The method further comprises performing frequency synchronization using a signal transmitted from a radio interface of the first base station and performing time synchronization using a signal transmitted from a radio interface of the second base station. In this manner, the synchronizing base station is enabled to independently select the first and second base stations used for frequency and time synchronization, respectively.

Abstract: Systems and methods related to time and frequency synchronization of a base station in a cellular communications network are disclosed. In some embodiments, a method of operation of a synchronizing base station comprises selecting a first base station for frequency synchronization and a second base station for time synchronization, where the second base station can be different than the first base station selected for frequency synchronization. The method further comprises performing frequency synchronization using a signal transmitted from a radio interface of the first base station and performing time synchronization using a signal transmitted from a radio interface of the second base station. In this manner, the synchronizing base station is enabled to independently select the first and second base stations used for frequency and time synchronization, respectively.

Abstract: A technique for managing activity states of at least two subscriptions in a terminal device is described. A method implementation of this technique performed in the terminal device comprises the steps of monitoring whether a first subscription is to transit or has transit from a first active state to a second active state while at least one second subscription is in a detached state, wherein the second active state is associated with a lower terminal activity than the first active state, if the result of the monitoring step is affirmative, waiting for a predetermined period of time, upon elapse of the predetermined period of time, if the first subscription is still in the second active state, triggering a transition of the first subscription from the second active state to an inactive state and initiating for the at least one second subscription a transition from a detached state to an inactive state.

Abstract: A carrier frequency offset calibration method and a carrier frequency offset calibration system are provided. The carrier frequency offset calibration method is adapted to calibrate the carrier frequency offsets of a transmission signal which includes a primary carrier and a secondary carrier. In the carrier frequency offset calibration method, the transmission signal is analyzed according to known carrier frequencies, a primary feedback value and a secondary feedback value, so as to obtain a primary carrier offset value and a secondary carrier offset value. The relationship between the primary carrier offset value and the secondary offset value is considered to determine whether to adjust the primary feedback signal and the secondary feedback signal.

Abstract: Receiver synchronization techniques (RST), contributing more accurate synchronization of receiver clock to OFDM composite frame combined with much faster acquisition time and better stability of the receiver clock, and phase and frequency recovery techniques, comprising a software controlled clock synthesizer (SCCS) for high accuracy phase & frequency synthesis producing synchronized low jitter clock from external time referencing signals or time referencing messages wherein SCCS includes a hybrid PLL (HPLL) enabling 1-50,000 frequency multiplication with very low output jitter independent of reference clock quality.

Abstract: A method for teaching a switching circuit is provided. The method includes presenting a target within a sensing range of a sensor of the switching circuit for a pre-determined duration and acquiring an identification code of the target via the sensor. The method also includes storing the acquired identification code for operating the switching circuit and locking the switching circuit against learning identification codes of any other target prior to reaching an allowed number of reteaching attempts.

Abstract: A medical device communication system transmitter may include a resonator coupled to a local oscillator for stabilizing an operating frequency of the local oscillator. A control device of the transmitter receives an open-loop control signal, and the local oscillator and the control device are configured to generate a direct modulated radio frequency transmission signal in response to the open-loop control signal.

Abstract: A multichannel combiner formed from 2 to 1 combiners, wherein: a first input channel of each 2 to 1 combiner is connected to the output of a settable-gain amplifier of a signal to be combined; all 2 to 1 combiners are electrically connected in series; and an output of a first 2 to 1 combiner defines an output of the multichannel combiner.

Abstract: A desired signal and interfering signal are transmitted in the same timeslot and on the same frequency using an Adaptive Quadrature Phase Shift Keying (AQPSK) modulated carrier. When the Sub-Channel Power Imbalance Ratio (SCPIR) for the AQPSK modulated carrier is large and favors the interfering signal, the interfering signal is demodulated first to obtain demodulated soft bits. The demodulated soft bits corresponding to the interfering signal are then used to estimate receiver control parameters, such as Doppler shift, frequency offset, timing error, gain, etc. Using the demodulated soft bits corresponding to the interfering signal improves the accuracy of the receiver control parameters when the SCPIR is large, and results in better overall performance of the receiver.

Abstract: Apparatus for generating a first signal (e.g., a pulse) including a current source adapted to generate a current based on a second signal that defines an amplitude of the current and a third signal that defines the timing of an amplitude change of the current, and an impedance element through which the current flows to generate the first signal. The impedance element may comprise a resonator having a resonant frequency approximate the center of the first signal frequency spectrum. An LO may be used to generate the third signal to control the timing of the amplitude change of the current. A detector may enable the current source in response to detecting a defined steady-state condition of the LO clock signal, and may disable the current source in response to the completion of the first signal. A controller may generate the second signal to control the current amplitude so as to perform power control and/or other functions.

Abstract: Disclosed is a transmitter for a communication system. The transmitter comprises a sidelobe suppression module configured to apply a suppression matrix to an input vector comprising symbols to be transmitted by the transmitter; a modulation module configured to modulate the precoded vector to a time-domain symbol using a plurality of subcarriers, each symbol in the precoded vector having a corresponding subcarrier; and a digital-to-analog conversion module configured to convert the time-domain symbol to an analog waveform for transmission. The suppression matrix is constructed such that emissions at one or more predetermined suppression distances lying outside a frequency band defined by the subcarriers are set to zero according to a predetermined emission model.

Abstract: In accordance with an example embodiment of the present invention, an apparatus comprises a first multiplier configured to convert a first frequency signal into a second frequency signal based at least in part on a first complex-valued local oscillator signal, a pair of low-pass filters configured to filter the second frequency signal, and a second multiplier configured to convert the filtered second frequency signal into a third frequency signal based at least in part on a second complex-valued local oscillator signal wherein the first frequency signal and the third frequency signal share the same frequency position and the pair of low-pass filters is configured based on an indication of allocated transmitted channels.

Abstract: A bang-bang frequency detector with no data pattern dependency is provided. In examples, the detector recovers a clock from received data, such as data having a non-return to zero (NRZ) format. A first bang-bang phase detector (BBPD) provides first phase information about a phase difference between a sample clock and the clock embedded in the received data. A second BBPD provides second phase information about a second phase difference between the clock embedded in the received data and a delayed version of the sample clock. A frequency difference between the sample clock and the clock embedded in the received data is determined based on the first and second phase differences. The frequency difference can be used to adjust the frequency of the sample clock. A lock detector can be coupled to a BBPD output to determine if the sample clock is locked to the clock embedded in the received data.

Abstract: Generate a series of digital data according to a pair of differential signals received from a low speed universal serial bus. Calibrate coarsely a frequency of an oscillator according to a width of an end-of-packet of the series of digital data. And calibrate finely the frequency of the oscillator according to a width of a SYNC pattern of the series of digital data.

Abstract: Provided are a receiver and a receiving method for a scalable bandwidth in a mobile station of an Orthogonal Frequency Division Multiplexing (OFDM) system. The receiving method includes the steps of: (a) filtering a received RF signal; (b) oscillating a frequency according to a center frequency control signal to output a local oscillation frequency; (c) down-converting the filtered RF signal by using the local oscillation frequency; (d) scalable-filtering the down-converted signal while adjusting a bandwidth according to a bandwidth control signal; (e) controlling gain of the scalable-filtered signal; (f) converting the gain-controlled analog signal into a digital signal by using a sampling frequency matching with a corresponding bandwidth according to an ADC control signal; and (g) demodulating the converted digital signal, outputting the center frequency control signal, the bandwidth control signal, and the ADC control signal according to control information received from an upper layer.

Abstract: A transmitter includes an encoding module, an adaptive hierarchical signal mapping module and a transceiver module. The encoding module receives an input signal and encodes the input signal. The input signal includes data to be transmitted. The adaptive hierarchical signal mapping module modulates the encoded signal according to one or more hierarchical level distance ratios to obtain modulated symbols. The hierarchical level distance ratio defines distances between the modulated symbols. The transceiver module generates a radio frequency signal according to the modulated symbols and transmits the radio frequency signal to an air interface.

Abstract: A clock generator circuit generates a wanted RF clock signal by using an up-converter, a spurious tone cancellation circuit, a controller, and at least two clock driver/dividers. The spurious tone cancellation circuit includes a tone detection circuit and a tone generation circuit. The up-converter mixes modulation signals with local quadrature RF clock signals to create an up-converted signal having a frequency tone equal to a desired frequency of the wanted RF clock signal. The first clock driver/divider amplifies and clips the up-converted signal into a first-clipped clock signal. The tone detection circuit detects the amplitude and phase of unwanted tones of the first-clipped clock signal in the baseband domain and provides information to the controller, which controls the tone generation circuit to cancel the unwanted tones and create a compensated version of first-clipped clock signal.

Abstract: A method and system of fine timing synchronization for an OFDM signal. The OFDM signal is coarse timing synchronized, generating a synchronization sequence and a CFR (Channel Frequency Response). The synchronization sequence is removed. A correlation coefficient of the correlation between the CFR applied to a number of carriers and the number of carriers with different window shifts is calculated. The largest window shift corresponding to a downsampling factor is indicated by the lowest correlation coefficient greater than a threshold. The CFR is downsampled by the downsampling factor, and an inverse FFT is performed on the downsampled CFR with a reduced number of calculations reduced by the downsampling factor, transforming the CFR into a CIR. A fine timing synchronization position is determined from the CIR and is utilized by an FFT unit within an OFDM receiver to accurately receive OFDM symbols of the OFDM signal.

Abstract: A mobile station (14) transmits a signal after connection is established, by using the same number of subcarriers as the number of subcarriers equal to or smaller than a predetermined number used for transmitting a connection request signal (TCCH). A base station (12) detects the number of subcarriers used for transmitting the connection request signal (TCCH) (S106), and controls in accordance with the detected number of subcarriers the passband width of a bandpass filter having a passband with a variable width accommodating the predetected number of subcarriers, for separating a signal of the mobile station (14) falling within the passband from a received signal (S108).

Abstract: Provided are a receiver and a receiving method for a scalable bandwidth in a mobile station of an Orthogonal Frequency Division Multiplexing (OFDM) system. The receiving method includes the steps of: (a) filtering a received RF signal; (b) oscillating a frequency according to a center frequency control signal to output a local oscillation frequency; (c) down-converting the filtered RF signal by using the local oscillation frequency; (d) scalable-filtering the down-converted signal while adjusting a bandwidth according to a bandwidth control signal; (e) controlling gain of the scalable-filtered signal; (f) converting the gain-controlled analog signal into a digital signal by using a sampling frequency matching with a corresponding bandwidth according to an ADC control signal; and (g) demodulating the converted digital signal, outputting the center frequency control signal, the bandwidth control signal, and the ADC control signal according to control information received from an upper layer.

Abstract: In a transmission apparatus, a comparison unit provides threshold values associated with an amount of data indicating a signal frequency, and compares an input parameter obtained by cumulatively adding a correction amount to the parameter with the threshold values. When the input parameter is within a range defined by the threshold values, a correction unit outputs a value of the input parameter. When the input parameter is out of the defined range, the correction unit outputs an associated one of the threshold values so as to eliminate an amount exceeding or falling short of the defined range, to thereby correct the input parameter. An addition unit detects the correction amount which is an amount of the immediately preceding value of the input parameter exceeding or falling short of the defined range, and cumulatively adds the correction amount to the input parameter used for the comparison of this time.

Abstract: A communication system comprising one or more transceiver units of a first type and one or more transceiver units of a second type capable of communicating with the transceiver units of the first type; each transceiver unit of the first type comprising: a frequency comparison unit for comparing the frequency of a signal received from a transceiver unit of the second type with a reference frequency; a feedback signal generator for generating a feedback signal dependent on the result of that comparison; and a transmitter for transmitting that signal to the transceiver unit of the second type; and each transceiver unit of the second type comprising: a local frequency reference unit on which the frequency of signals transmitted by it are dependent; and a frequency adjustment unit for receiving the feedback signal and adjusting the local frequency reference unit in dependence on the feedback signal.

Abstract: A Radio Frequency (RF) transmitter and a signal amplification method therefor are provided, in which a signal source generates a signal of a predetermined Intermediate Frequency (IF) band, a local oscillator generates a signal of a predetermined high frequency band as a carrier signal, a power amplifier amplifies the signal received from the local oscillator to a predetermined transmission level, and a parametric mixer module receives the signals from the signal source and the power amplifier and outputs the received signals as a radio signal for transmission. The signal output from the parametric mixer module is transmitted as the radio signal without additional amplification.

Abstract: Certain embodiments of the present disclosure provide a method for frequency-domain gain control in system utilizing orthogonal frequency division multiplexing (OFDM) multiple input multiple output (MIMO). The proposed method reduces the complexity of the system while maximizing the internal accuracy of the OFDM MIMO decoder and preserving the performance of the system.

Abstract: A method for compensating a transceiver for impairments includes transmitting a plurality of partial bandwidth training signals using a transmitter. A plurality of response signals of a receiver having a bandwidth and exhibiting receiver impairments is captured. Each response signal is associated with one of the partial bandwidth training signals. Each of the partial bandwidth training signals is associated with a portion of the receiver bandwidth. A plurality of partial compensation filters is generated based on the plurality of response signals. Each partial compensation filter is associated with one of the response signals. The partial compensation filters are combined to configure a receiver compensation filter operable to compensate for the receiver impairments.

Abstract: A frequency synthesizer of a transceiver for generating a crystal oscillation frequency and a carry frequency having been done a process of frequency offset cancellation with that of another transceiver. The frequency offset cancellation of the frequency synthesizer is done in accordance with a wireless signal which is transmitted from another transceiver received. The frequency synthesizer has a first sigma-delta modulator receiving a signal transmitted by a transceiver at far area responding thereafter a frequency divisor value in accordance with the channel information of the received signal and a frequency offset between two.

Abstract: According to one aspect of the present invention, an apparatus is provided to enable weather band radio signals to be received and processed using a digital signal processor (DSP). The DSP can include functionality to implement both frequency modulation (FM) demodulation and weather band data demodulation, i.e., specific area encoding (SAME) demodulation. In one such embodiment, soft decision samples of a SAME message can be combined, and based on a combined result, a hard decision unit can generate a bit value of weather band data.

Abstract: A battery pack is provided which includes an antenna coil for generating a magnetic field, a battery cell and a positive pole terminal and a negative pole terminal electrically connected with the battery cell, wherein a resultant of superimposing current from the battery cell or current to the battery cell and a signal from the antenna coil or a signal to the battery is sent from the positive pole terminal or the negative pole terminal, or received from the positive pole terminal or the negative pole terminal.

Abstract: Methods for processing a signal of interest in an electrical power system are provided, as well as systems and computer program products for carrying out the methods. The methods include obtaining a representative window of data points from the signal of interest; obtaining a window of interest containing data points from the signal of interest; and comparing a phase drift compensated window to the representative window, wherein the compensated window is calculated in accordance with the window of interest and a phase drift that is present in the window of interest relative to the representative window.

Abstract: A transceiver is provided for wireless communication. The transceiver can include a bias source, a transformer including a primary side and a secondary side, and a switching device. During a receive mode, the primary side of the transformer is configured to receive a first signal from a first port. During a transmission mode, the primary side is configured to transmit a second signal from a second port. The switching device is configured to couple the first port to the bias source during transmission of the second signal and to couple the second port to the bias source during receipt of the first signal. The bias source can be, for example, ground.

Abstract: This invention provides a wireless transmitter circuit for mobile communication apparatus and this circuit can be configured with fewer components and is suitable for downsizing. A single PLL synthesizer serves as both RF frequency band PLL and IF frequency band PLL among three oscillators for TX, RX and IF frequency bands, which have been required in conventional mobile communication apparatus. The number of necessary oscillators occupying a large area within a chip is reduced and the number of components is decreased. Specifically, circuitry is arranged to generate local oscillation signals for RF and IF frequency bands by frequency dividing the output of a VCO of the RF frequency band PLL.

Abstract: A power amplifier controller circuit controls a power amplifier based upon an amplitude correction signal indicating the amplitude difference between the amplitude of the input signal and an attenuated amplitude of the output signal. The power amplifier controller circuit comprises an amplitude control loop and a phase control loop. The amplitude control loop adjusts the supply voltage to the power amplifier based upon the amplitude correction signal. The RF power amplifier system may reduce the corrective action of the amplitude loop during periods of relatively rapid changes in amplitude, and thus distortion can be further reduced.

Abstract: In a control method of a communication system, a Base Station (BS) receives noise and interference information from at least one neighboring BS in charge of a neighboring cell being adjacent to a serving cell of the BS, calculates a control value of Mobile Stations (MSs) located in the serving cell according to the received noise and interference information, and generates control information according to the calculated control value, and transmits the generated control information to the MSs.

Abstract: A frequency synthesizer (100) can selectively set an output band of VCO, and consumes less power. The frequency synthesizer (100) has a frequency converting circuit (110) that has a mixer (111) and a frequency divider (112) connected with each other in parallel. The frequency synthesizer (100) uses the frequency divider (112) upon frequency band selection in VCO (101) and uses the mixer (111) upon transmission.

Abstract: A communications transmitter having a main transmit chain for main signal features and one or more auxiliary transmit chains for auxiliary signal enhancements. In one embodiment, a communications signal is produced by digitally processing a representation of a desired signal so as to limit a trajectory of a signal represented by a resulting processed signal. A digital representation of a difference signal approximating a difference between the processed signal and the desired signal is produced. A first modulated, amplified signal is produced in dependence on the processed signal, and a second modulated, amplified signal is produced in response to the difference signal. The first modulated, amplified signal and the second modulated, amplified signal are combined to produce the desired signal. In this manner, a main transmit chain may be optimized with respect to other properties than signal quality (e.g.

Abstract: A signal conversion apparatus includes a local oscillator for locally generating a signal having a frequency, a phase shifter for shifting the phase of the locally generated signal output from the local oscillator by an amount determined based on a relationship between the amount of phase shift and the amount of frequency pulling, and a converter for converting an input signal by using the phase-shifted locally generated signal output from the phase shifter. The phase shifter varies impedance between the local oscillator and the converter so that the oscillating frequency of the locally generated signal output from the local oscillator remains unchanged.

Abstract: Excessive quality in the receiving apparatus is controlled to obtain the combined gain by distinctively controlling the re-transmission for the first transmission. A transmitting apparatus for transmitting the data to a receiving apparatus to execute regeneration of data using, for example, the received data and the re-transmitted data, comprises a control unit operable to receive an indication that an error has been detected in received data transmitted in a first transmission, to re-transmit the data in a second transmission, and to control resources for re-transmission of the data to use fewer resources for the second transmission than for the first transmission.

Abstract: In accordance with an example embodiment of the present invention, an apparatus comprises a first multiplier configured to convert a first frequency signal into a second frequency signal based at least in part on a first complex-valued local oscillator signal, a pair of low-pass filters configured to filter the second frequency signal, and a second multiplier configured to convert the filtered second frequency signal into a third frequency signal based at least in part on a second complex-valued local oscillator signal wherein the first frequency signal and the third frequency signal share the same frequency position and the pair of low-pass filters is configured based on an indication of allocated transmitted channels.

Abstract: A chip comprises and operational section and an input/output section. The operational section includes a controller. The input/output (I/O) section is coupled to the operational section. The I/O section comprises a transformer and a switching device. The transformer includes a primary side connected to first and second I/O ports and a secondary side connected to the operational section. The switching device is coupled to the controller and between the first and second I/O ports and a bias port, such that, under control of the controller, the switching device connects one of the first and second I/O ports to the bias port.

Abstract: According to an aspect of the invention, an oscillating circuit includes: a first MOS transistor having a first drain terminal and a first source terminal; a load element connected to the first drain terminal; and an oscillator connected to the first source terminal and outputs a fundamental signal and a harmonic signal, wherein the harmonic signal is amplified so that the amplified harmonic signal is output from the first drain terminal.

Abstract: A device and method for synthesizing a transmission frequency (a Tx frequency) in a wireless terminal are provided, which are designed for stably operating a Phase Locked Loop (PLL) in order to synthesize a Tx frequency for a certain channel.

Abstract: A method processes defects in a radio frequency transmission subsystem due to elements therein. The defects may include mismatch between two channels in phase quadrature in the transmission subsystem and a transposition signal leaking from a first frequency transposition stage of the transmission subsystem. The method may include calibration processing including estimating compensation parameters representative of the defects. The estimating may include delivering, into the transmission subsystem upstream of the elements creating the defects, a reference signal having a reference frequency, obtaining, downstream of the first transposition stage, of a resultant reference signal, and obtaining, from the resultant reference signal, of an approximate value for each compensation parameter. The method also may include compensating for the defects by injecting the approximate values into the transmission subsystem.

Abstract: A method and system for generating noise in a frequency synthesizer are provided. The method includes generating a noise portion of an input signal within the frequency synthesizer and appending the noise portion to a control portion of the input signal.

Abstract: A communication system that includes a Multimedia Broadcast Multicast Service (MBMS) service provides re-broadcasts of an event to subscribers to the MBMS service. An infrastructure included in the communication system and comprising a server coupled to a RAN controller via a support node receives a first set of MBMS data from an MBMS content provider and conveys the first set of MBMS data along with an associated first Session Description to a subscribed mobile station. The infrastructure then receives a second set of MBMS data from the MBMS content provider, wherein the second set of MBMS data comprises a re-conveyance of the first set of MBMS data, and conveys an MBMS notification along with an associated second Session Description to the mobile station. The mobile station may then determine whether to receive the re-conveyance based on the first and second Session Descriptions.

Abstract: A transmission arrangement is provided for transmitting data continuously in the time domain. The arrangement includes at least one programmable amplifier in the baseband or in the radio frequency path in the signal processing chain for the signal which is to be transmitted. This programmable amplifier is distinguished in that the signal which actuates the programmable amplifier is a discrete-value signal. By dispensing with complex digital/analog converters, the principle described allows markedly reduced power consumption in transmitters which use code multiple access methods.