Abstract: The invention relates to a code-tracking method and a rake receiver for CDMA communication systems of low complexity yielding stable tracking. Received signal are distributed to a plurality of receiver fingers of a rake receiver. Each receiver finger i is assigned to a signal path of the transmitted signal which is subject to phase shift and power dissipation due to reflection, diffraction and scattering. According to the invention in each receiver finger i an estimation of the timing delay {circumflex over (?)}(i) is provided and interference from other signal components j are subtracted from signal components of the current signal path i (i?j) yielding a reliable estimated timing delay {circumflex over (?)}.

Abstract: Method and system are disclosed for providing advanced RAKE delay control in wireless communications systems. The RAKE delay control method and system of the invention is capable of tracking presently known paths over time and merging the tracking results with new path searcher results. The invention is particularly suitable for devices where the resources (e.g., computational load, power) available for detecting the multipath components are limited. The result is a resource efficient architecture for positioning the RAKE fingers to best extract the signal power available in the channel and to utilize the inherent diversity due to the multipath nature of the signal.

Abstract: Crosstalk can be cancelled in a composite communication signal (ym) which includes a primary signal component associated with communication data and which also includes a crosstalk signal component produced by applying a crosstalk coupling function to crosstalk data. An estimate (R, RCb(0), RCb(?f)AVG) of a statistical characteristic of the crosstalk signal component is obtained from the composite communication signal. A cancellation signal (26, 46) is generated based on the statistical characteristic estimate, and an estimate (29) of the communication data is produced based on the composite communication signal and the cancellation signal.

Abstract: A decorrelating rake receiver (401) using a signal processor (213) and corresponding method (1000) to determine filter coefficients (1005). The decorrelating rake receiver includes a plurality of filters (219) arranged to be coupled to an input signal (403) and the filter coefficients (409), the plurality of filters operable to provide a plurality of output signals and a coefficient generator (407), coupled to the input signal, to explicitly and definitely determine the filter coefficients for the plurality of filters such that the plurality of filters perform a decorrelating rake process. The decorrelating rake receiver further includes a combiner (221) to combine the plurality of output signals and provide a received signal (405). The decorrelating rake receiver (401) is suitable for use in a wireless communication device (101) or base transceiver (103).

Abstract: A synchronization code detecting apparatus is designed for synchronization code detection in cell search in a code division multiple access (CDMA) system. The synchronization code detecting apparatus mainly includes a compensation unit for providing frequency offset compensation to the incoming signal and for determining a plurality of sampling points of the incoming signal. A plurality of sub-detecting units is coupled to the compensation unit for detecting a synchronization code of the incoming signal transmitting from the compensation unit. A selection unit is coupled to the output of each sub-detecting unit for selecting a plurality of slot boundaries as a plurality of candidates to be forwarded to a second processing stage. Consequently, the synchronization code detecting apparatus effectively reduces the effect of clock offset in the system without increasing the hardware complexity and power consumption.

Abstract: A complementary code decoder technique is provided where the encoded input data is first parallelized. From the parallelized data, correlation values are generated by a correlator circuit that is capable of changing its correlation characteristics depending on at least one control signal. Different control signals are sequentially provided to the correlator circuit thereby driving the correlator circuit to sequentially generate multiple correlation values from the parallelized data, based on different correlation characteristics. From the multiple correlation values, the correlation value that represents the optimum correlation is identified. This technique significantly reduces the gate count of the decoder structure, thus saving chip area and manufacturing costs.

Abstract: The receiving device of the invention contains a correlational operation unit that executes a correlational operation between a first modulated signal having a spread-spectrum modulation applied and a first spread-spectrum signal string to output a correlational signal, and a decision circuit that decides an amplitude value of the correlational signal to output a decision signal. The decision circuit is composed of: a first detector that outputs a first detection signal when it detects that a value of the first correlational signal exceeds the first threshold, a second detector that outputs a second detection signal when it detects that the value of the first correlational signal exceeds the second threshold, and a detected signal selector that outputs the decision signal of a first value when the first detection signal is inputted, and outputs the decision signal of a second value when the second detection signal is inputted.

Abstract: This invention generates pseudo-noise (PN) codes that map a transmitted data rate into the PN code structure. This invention further then acquires the PN code to automatically discover the transmitted data rate. This invention is operable with communication systems that utilize GPS time synchronization of the transmitted and received PN codes, as well as with communication systems where GPS time synchronization is not available. A method and a system are disclosed to transmit a modulated signal from a transmitter to a receiver, where the modulated signal has a data rate. The method includes selecting, to represent the data rate, at least one PN component code from a set of PN component codes. The PN component code is a constituent code of a composite PN code comprised of a plurality of PN component codes. The selected PN component code is one that phase aligns with a PN composite encoded signal.

Abstract: A GPS receiver having a ratio-based signal acquisition method. The GPS receiver has a tentative signal acquisition when a first ratio of the largest GPS signal correlation value to the second largest in a first time period exceeds a selected qualification ratio. The GPS receiver verifies signal acquisition when the average of iteration ratios for largest to second largest correlation values in iteration time periods exceed the qualification ratio.

Abstract: Burst detection with high accuracy is achieved with a single autocorrelation circuit. Autocorrelation is performed using a preamble-embedded correlation sequence chosen such that a steeply sloped peak characterizes the autocorrelation response. The autocorrelation circuit is preferably used multiple times per clock period to deliver correlation moduli at sub-clock multiples. A contrast function makes a weighted comparison of each correlation modulus output by the autocorrelation circuit relative to adjacent correlation moduli. The contrast output defines a burst start-time uncertainty-window in a manner that is independent of signal level variability attributable to different operating conditions. A search is performed within the uncertainty window to identify the correlation maximum. Depending on the system mode (e.g., traffic mode vs. ranging mode), a priori knowledge may be preferred to the contrast output for defining the timing uncertainty window of the search.

Abstract: An OFDM receiver includes an offset compensator (14) compensating for a frequency offset in a received OFDM signal. The offset compensator (14) includes a memory (51) storing two reference signals corresponding to arbitrary portions in the start symbol of the OFDM signal. A cross correlation value between the received OFDM signal and each of the two reference signals is calculated by a cross correlator (52, 53). Each peak position is detected by a peak detector (54). A frequency offset estimate value of the received OFDM signal is estimated by a frequency offset estimation circuit (55) based on the cross correlation value at each detected peak position. A phase rotation circuit (37) compensates for the frequency offset of the received OFDM signal based on the estimated frequency offset estimate value.

Abstract: A method for synchronizing a base station to a mobile station includes transmitting a signal sequence K(i) of length n from the base station to the mobile station. The signal sequence K(i) is formed by repeating a second signal sequence element K2(k) of length n2 n1 times. The second signal sequence is modulated with a first signal sequence element K1(j) of length n1. In the method, n1 is equal to n2 and i, j and k are integers.

Abstract: The present invention is related to a mobile telecommunication system, and more specifically, to a multi-peak detector of the mobile telecommunication system and a method thereof for high-speed acquisition of paths necessary for a timing synchronism using a hardware multi-peak detector. The peak detector according to the present invention can include a circuit that cumulatively saves a plurality of energy values that have been calculated through a matched filter and a squarer, and a circuit that outputs several energy values out of the cumulatively saved plural energy values, which are saved based on a high-ranked enable control signal and a high-ranked mask signal.

Abstract: A code division multiple access (CDMA) communication system using spread spectrum signaling over a communication bandwidth uses two different signal spectra generated using two different respective spreading code formats, such as NRZ code formatting and Manchester code formatting, for respectively providing nonsplit spectra having a center peak and split spectra having a center null. The spectra are combined during transmission as a CDMA communication signal having a composite spectrum. The use of different code formats produces the composite spectrum of respective center peak and center null spectra that enables increased channel capacity.

Abstract: A system for detecting and identifying the identity of a base station or cell which transmits a scrambling code is provided. According to one aspect of the system, the system is used to perform scrambling code detection of eight (8) primary cells (each scrambling code being spaced sixteen (16) chips apart) in a group. According to another aspect of the system, a single scrambling code generator is used to generate a master scrambling code. The master scrambling code is then used to create individual scrambling codes which are used in correlation with received signals to detect in parallel which one of the eight (8) possible primary cells in the group transmitted the received signals.

Abstract: A civil moderate (CM) code and a civil long (CL) code are time division multiplex (TDM) as a combined code having alternating code chips that spectrum spread a transmitted signal received by a receiver tracking the spectrum spreading code using a two-level correlator operating with +1 and ?1 values to alternately correlate the received CM and CL code chips using a gating signal to gate by time the correlation of the two codes. The time gated two-level TDM correlation can be used in communication receivers, such as GPS receivers, receiving the TDM spectrum spreading codes.

Abstract: An apparatus and method of determining a signal code. The method comprising steps of acquiring and correlating a signal with a first code sequence. In response to the correlation of the signal with a first code sequence a timing lock is achieved. Also in response to the signal correlation, an acknowledgement from a receiver of the signal to a transmitter of the signal is sent where upon the receiver and transmitter change to a second code sequence.

Abstract: A method of wirelessly communicating between units comprises using at least two repeaters between a transmit unit and a receive unit. The repeaters enable a diversity scheme to be emulated.

Abstract: An impulse response of a channel is estimated by cross-correlating a known training signal with a received training signal to produce a cross-correlation vector. The cross-correlation vector is characterized by a known noise component resulting from the finiteness of the correlation. A correction vector is estimated based on the known training signal, where the correction vector is related to the noise component. Truncated representations of the correction vector are iteratively subtracted from the cross-correlation vector in order to produce a succession of cross-correlation outputs of increased accuracy. When the cross-correlation output is sufficiently accurate, it may be used to determine the weights to be given to the taps of an equalizer.

Abstract: The present invention discloses a method for searching multipaths of a mobile communication system, which includes the steps of: performing a coherent detection on a reversed I and Q channel signals of a DPCCH transmitted form a mobile station, multiplying the detected signal by a pilot pattern to accumulate a pilot symbol section in a corresponding section, and performing a coherent accumulation on the other symbol section in a symbol basis; calculating energy value for each coherently accumulated I and Q channel signals; multiplying the calculated energy values by a weight that has been multiplied by the pilot symbol section and another weight that has been multiplied by the other symbol section, respectively; noncoherently accumulating the energy values multiplied by variable weights, and saving the energy values; comparing the saved energy values with a periodically designated threshold; and searching timing information as many as a number of fingers in order of highest energy value according to the compa

Abstract: The CDMA communication system according to the invention comprises at least one primary station (2) and a plurality of secondary stations (4). The primary station (2) and the secondary stations (4) can exchange CDMA signals (18) via a communication medium (6). The secondary stations (4) each comprise a modulator (10) for modulating data signals (16) with code words (14) in order to obtain the CDMA signals (18). A modulator (10) of a secondary station (4) initially modulates its data signal (16) with an initial code word until that secondary station (4) is synchronized with the primary station (2). From that moment on the data signal (16) is modulated with a final code word. Ideally, an initial code word is used which is, for every possible time shift of that code, substantially orthogonal to all the final code words in use by the already synchronized secondary stations (4).

Abstract: A demodulator in a wireless communication network for combining symbols without the need to store the received symbols in buffers for subsequent retrieval and accumulation. The demodulator includes a plurality of accumulators capable of accumulating received symbols, each symbol associated with a physical channel and a propagation path. The demodulator includes a multiplexer for routing the received symbols to an appropriate accumulator selected from the plurality of accumulators. The symbols received from different propagation paths are each routed and accumulated to an appropriate accumulator based on a physical channel of the received symbol and a value of an indicator associated with a propagation path of the received symbol.

Abstract: An exemplary signal processing system determines vector mismatch between a plurality of signal paths. Advantageously, the system can determine mismatch across a range of frequencies. A signal generator of the system can provide a periodic calibration signal having a plurality of frequency components. The system frequency can translate the calibration signal to provide a first set of observed samples. The first sample set can be compared to a second set of samples, which can be modeled by a function of parameters including an estimated vector mismatch and a plurality of basis functions. A value of vector mismatch can then be determined (at least to an estimate) that minimizes the difference between the first sample set and the second sample set. Methods and other systems with different advantageous configurations are also described.

Abstract: The invention relates to a reception method and a receiver in a system comprising in each cell a base station communicating with terminals located in its area. A received signal comprises a sum signal of signals originating from several transmitters. The receiver comprises means for performing interference elimination and a simultaneous multi-user detection to the signal and means for searching signal parameters. In order to reduce the required computational capacity, the receiver further comprises means for removing the effect of the signals of the known users from the receives sum signal, and means for estimating the parameters of the unknown signals from a narrowband residual signal.

Abstract: A system and method suppresses the interference caused by non-orthogonal signals on multiple channels of the same receiver by applying an inverse of the correlation among the non-orthogonal signals to the decoded signals. In a multi-channel receiver, the receiver is aware of the codes that are allocated to each of the channels, and thus, can be configured to determine the correlation among the multiple codes that are allocated to a receiver. The inverse of this correlation is applied to the output of the correlators assigned to each code, thereby suppressing the effects of using non-orthogonal codes for transmissions to the same receiver. If different sized codes are allocated to the same receiver, the correlation of the shorter code and a corresponding segment of the longer code is computed. The inverse of the correlation for the segment is applied to the output of the correlators, corresponding in time to the processing of the shorter code and this segment of the longer code.

Abstract: The receiver (1) for radio-frequency signals (SV1, SV2, SV3, SV4), modulated by specific codes of transmitting sources, such as satellites (S1, S2, S3, 54), includes receiving and shaping means with frequency conversion for the radio-frequency signals for generating intermediate signals, a correlation stage formed of several correlation channels for receiving the intermediate signals and microprocessor means connected to the correlation stage in order to process the extracted data after correlation. Each channel includes a correlator in which the intermediate signals are correlated with at least two early and late replicas of the specific code of a visible transmitting source to be searched and tracked. The correlator further includes integrator counters for the correlated signals to provide a first amplitude value of the auto-correlation function of the early signals and a second amplitude value for the late signals.

Abstract: A method including searching for a pilot signal of a second communications system while retaining the connection with a first communications system.

Abstract: A power threshold value (12) is set to be compared with a correlation power value detected by a correlator (2) and a power conversion section (4). As a result of comparison by a comparator (13), only the correlation power values that exceed the threshold value (12) are stored in a power value memory (14), and unnecessary correlation values at noise levels are not stored in the memory (14) so that the number of power values stored can be decreased. With this construction, the necessary memory capacity can be decreased, and the process of searching for the maximum value from the correlation power values stored in the memory (14) can be performed at a higher speed.

Abstract: A Node-B/base station has a path searcher and at least one antenna for receiving signals from users. The path searcher comprises a set of correlators. Each correlator correlates an inputted user code with an inputted antenna output of the at least one antenna. An antenna controller selectively couples any output of the at least one antenna to an input of each correlator of the set of correlators. A code phase controller selects a user code for input into the set of correlators. Each delay of a series of delays delays the selected user code by a predetermined amount and each correlator of the set of correlators receives a different code phase delay of the selected user code. A sorter and path selector sorts the output energy levels of each correlator of the sets of correlators and produces a path profile for a user based on the sorted output energy levels.

Abstract: In a radio signal transmitter, a microcomputer operates by receiving an output voltage of a battery to sequentially generate a voltage boosting control signal. This voltage boosting control signal has a longer high level period as generated later. The voltage booster circuit boosts the output voltage of the battery by increasing the number of times of oscillating operations during the high level period of the voltage boosting control signal depending on the increased high level period.

Abstract: A system and method for fast synchronization of an incoming signal with a UWB receiver rapidly. The present invention synchronizes with a UWB receiver with an incoming signal. The present invention correlates a local pulse generated at the receiver with the incoming signal, finds a phase angle in the correlation function that would correspond to a high signal to noise ratio, thereby matching the receiver to the incoming signal phase, and operates the receiver at that phase. Exemplary options of fast synchronization include using multiple detection arms to compare one parameter of the correlation function to a predetermined threshold.

Abstract: In a multi-path detection circuit for use in a CDMA communication system, a first peak is detected by searching a maximum value over a whole of data blocks composed of delay profile data. A second and the following peaks are detected by carrying out maximum value searching operation again only about a data block that is renewed in the delay profile data. As the remaining data blocks, a maximum value searched a previous time is preserved and used a next time and, therefore, reduction is possible in connection with the number of detection cycles necessary for detecting the second and the following peaks.

Abstract: Disclosed are a method of estimating a Doppler frequency shift and a method of transmitting data using the same. The method of estimating the Doppler frequency shift includes the steps of calculating difference values of a received pilot signal between i-th slot and (i?1)-th slot, for i=1, 2, . . . , N; and estimating a Doppler frequency shift based on the difference values.

Abstract: A received wireless signal contains a plurality of path components, each having a phase indeterminate data stream derived from an original data stream. The receiver splits the received signal into N signal copies for N raking channels, which correlate each of the N signal copies with N locally generated signals, respectively, to generate N correlated signals. Each of the N correlated signals carries an estimated phase indeterminate data stream. The raking channels then synchronize each of the correlated signals to a system clock in phase and frequency to generate N synchronized signals. The N raking channels then align the N synchronized signals to generate N aligned signals, each of which carries an aligned path data stream that is normalized in time with respect to the other aligned signals. Finally the receiver combines the aligned signals to produce an estimated original data stream.

Abstract: A method (400) and a receiving unit (220) for demodulating a multi-path signal are described herein. The receiving unit (220) may be configured to receive the multi-path signal. The receiving unit (220) may include an input buffer controller (305), an input buffer (310), a rake finger (330), and a sum generator (340). The input buffer (310) may be configured to store data samples associated with a plurality of paths of the multi-path signal. The input buffer controller (305) may be configured to time-align the data samples relative to each other, and to delay the data samples. The rake finger (330) may be configured to de-spread and to accumulate the delayed data samples for a sub-correlation length. The sum generator (340) may be configured to combine a plurality of outputs from the rake finger (330). Each of the plurality of outputs corresponds to one of the plurality of paths of the multi-path signal.

Abstract: A bypass circuit around a filter and RF amplifier of a front end device is activated when a received signal strength (RSS) passes a threshold in which the filter and RF amplifier are not necessary to filter/boost the received signal for processing in subsequent electronics (mixers, SAW filters, AGC amps, etc). A control device compares the RSS to the threshold and activates the bypass circuit. The bypass circuit is a switch coupled between an input of the filter and an output of the RF amplifier. The RF amplifier is shutdown when the bypass circuit is activated. The present invention may be used in combination with an LNA bypass to further decrease power consumption.

Abstract: The present invention provides a search window delay tracking procedure for use in a multipath search processor of a CDMA radio receiver. A channel impulse response is estimated for a received signal containing plural paths, each path having a corresponding path delay. A search window defines a delay profile that contains the plural paths of the received signal. A mean or average delay is calculated for the estimated channel impulse response (CIR), and an error is determined between the mean CIR delay and a desired or target delay position of the Cir. search window. An adjustment is made to reduce that error to align the targeted position of the search window and the mean CIR delay. A Doppler frequency is estimated for each path. The adjustment is made taking into account a Doppler effect caused by relative movement between the transmitter and receiver.

Abstract: To provide an apparatus for calculation of correlation that can take a correlation even when a frequency error is relatively large. With a 0-th degree correlator for taking, to output, a correlation between a reference signal and a measurement signal, an n-th degree correlator including an ejwt multiplier of calculating a frequency component addition signal having a frequency component added to the reference signal, and a correlation calculator for taking, to output, a correlation between the frequency component addition signal and the measurement signal, and an adder for adding an output of the 0-th degree correlator and an output of the n-th degree correlator and the output of the n-th degree correlator added at the adder do not have an increased noise/correlation value ratio, even when a frequency error is large. Accordingly, a correlation can be taken even with an increased frequency error. Another embodiment includes a conceptual block diagram in which a symbol D(o) is multiplied by a frequency.

Abstract: In a spread spectrum communication using a long spreading code, a spread spectrum signal processing apparatus is provided, which is suitable for performing communication by using a correlator having a size mountable on a portable equipment. The spread spectrum signal processing apparatus has a correlator for correlating between a spread spectrum signal and a given reference signal, an A/D converter for converting a correlation signal into a digital signal, a memory for storing the digital signal from the AD converter as digital data, a signal processor for summing digital data corresponding to each of divided codes C1–C16 and for outputting a result of summation, and a control unit for controlling to apply each of the divided codes C1–C16 in this order repeatedly as a reference signal to the correlator. The signal processor begins a summing process by making reference to a timing signal from the control unit.

Abstract: A path searcher of a spread spectrum receiver includes a number of correlators each of which produces a replica of a scrambled synchronization code and determines a correlation between the replica and a received spread spectrum signal. Each of the correlators performs a correlation operation between the received spread spectrum signal and the replica at a rate higher than a chip rate of the spread spectrum signal by successively shifting the replica with respect to the spread spectrum signal.

Abstract: In order to perform synchronization detection with high speed, high precision and high reliability and to measure communication quality (propagation characteristics) at high precision and high efficiency, a mobile station includes synchronization detecting portion for detecting synchronization chip timing of channel to be measured, a synchronization chip timing information portion accumulating information of detected synchronization chip timing, a correlation detecting portion deriving a correlation value between spreading code of the channel to be measured and a received signal for performing communication with a base station and measurement of communication quality with taking the detected synchronization chip timing as a reception chip timing, a time series generating portion for generating a time series data of received signal vector after correlation detection, and a communication quality calculating portion for calculating communication quality from generated time series data.

Abstract: Methods and apparatus are presented for improving the feedback of channel information to a serving base station, which allows a reduction in the reverse link load while allowing the base station to improve the forward link data throughput. Over a channel quality indicator channel, three subchannels are generated; the re-synch subchannel, the differential feedback subchannel, and the transition indicator subchannel. The information carried on each subchannel can be used separately or together by a base station to selectively update internal registers storing channel conditions. The channel conditions are used to determine transmission formats, power levels, and data rates of forward link transmissions.

Abstract: A path detection method comprises; a correlator which receives input of a baseband signal converted to a digital signal in a wireless receiver, and which takes a reverse spread produced by the multiplication of the baseband signal and a spread code pilot symbol and outputs a correlation signal; an in-phase adder which, in each time slot, adds the correlation signal for the time slot a predetermined number of times, a first addition results storage memory for adding for the predetermined number of times, a second addition results storage memory for storing the addition results from the aforementioned in-phase adder when the addition is completed the predetermined number of times in the aforementioned time slot, an electric power adder for batch reading the results for each time slot from the aforementioned second addition results storage memory and performing addition, and a path detection apparatus which executes a path detection according to the output of the aforementioned electric power adder.

Abstract: A multiple integration hypothesis C/A code acquisition system resolves bit boundaries using parallel correlators providing magnitude hypotheses during acquisition to reduce losses over the 20 ms integration period to improve the performance and sensitivity of C/A code receivers to achieve low C/No performance using inexpensive, imprecise oscillators and long noncoherent dwell periods, well suited for in-building, multipath, and foliage attenuated GPS signaling applicable to E911 communications with several dB of additional improvement in receiver sensitivity due to the ability to detect bit synchronization during acquisition.

Abstract: A synchronization establishing and tracking circuit for a CDMA base station is composed of a first spreading code generator, a first correlator, a second spreading code generator, a second correlator, and a phase determining circuit. The first spreading code generator generates a first spreading code sequence. The first correlator calculates first correlation between the first spreading code sequence and a first quasi-coherent signal corresponding to a first received signal received by the CDMA base station. The second spreading code generator generates a second spreading code sequence. The second correlator calculates second correlation between the second spreading code sequence and a second quasi-coherent signal corresponding to a second received signal received by the CDMA base station. The phase determining circuit determines a first phase of the first spreading code sequence based on an added quasi-coherent signal to which the first and second quasi-coherent signals are added.

Abstract: There is provided a correlation method for spread spectrum signals. Correlation peaks in packet headers included in the spread spectrum signals are detected by averaging known signals that repeat in the packet headers. Data corresponding to the spread spectrum signals is recovered based on the correlation peaks.

Abstract: A method for managing a code sequence according to a first embodiment of the present invention is disclosed. Sets of n contiguous sample values that include sample values in a plurality of sample sequences are accessed. Sets of n contiguous coefficients are accessed. The sample values in each of the plurality of sets of sample values that are accessed are processed in parallel with corresponding coefficients that are accessed. Each of the plurality of sets of sample values are processed during a different time step.

Abstract: A CDMA radio receiving apparatus which receives a slot which has a long code group identification short code at a point where a long code is masked. The apparatus includes a detector that detects a phase of the long code in association with a pattern that appears over successive slots and comprises the long code group identification short code. The apparatus also includes a correlator that performs correlation processing in association with the phase detected by the detector to identify the long code.

Abstract: A method and communications receiver is disclosed that removes Doppler frequency shift in a spread spectrum communications signal. A pilot channel rake section has I and Q Doppler estimation channels for estimating the Doppler change in frequency based on a common pilot channel. A data channel rake section has I and Q data channels for receiving the Doppler change in frequency from the pilot channel rake section and canceling any Doppler error.

Abstract: A fast initial acquisition and search device for a spread spectrum communication system is disclosed herein. The search device includes a memory for storing the first code sequence, and a plurality of computation circuits coupled in parallel to the memory. The search device also includes a plurality of threshold detector circuits. Each of the plurality of threshold detector circuits is respectively coupled to one of the plurality of computation circuits. Each of the plurality of computation circuits implements a unique phase offset for a second code sequence with respect to the first code sequence. A correlation operation is performed in parallel at each of the plurality of computation circuits followed by a threshold evaluation that indicates whether the correlation result satisfied a threshold value.