Abstract: The invention relates to a mobile system in which the radio interface rate of a traffic channel and the intermediate rate of a transmission channel restrict the number of bits available for the transmission of terminal interface statuses (S), network independent clocking (N) and subchannel numbering (#) of a multichannel data link. In the invention, the bits form a subframe (n, . . . , n+10) and the status and control information are multiplexed inside successive subframes in a superframe structure (SUPERFRAME). In other words, the capacity of the bits available for the control information is shared by various kinds of control information by means of the superframe structure.

Abstract: The method has two possible transmission modes: a first mode whereby a first transmitter (1) sends frames including sufficient auxiliary data to enable a first receiver (2) to acquire frame synchronization in a reliable fashion, said auxiliary data including a synchronization pattern, a second mode in which said first transmitter sends frames including insufficient auxiliary data to enable said first receiver to acquire said frame synchronization in a reliable fashion but, by virtue of a knowledge of said frame synchronization acquired previously, in said first mode, enabling loss of frame synchronization to be determined, loss of frame synchronization by said first receiver being signalled to said first transmitter by a second transmitter (15) changing from said second transmission mode to said first transmission mode and by a second receiver (16) detecting said change of transmission mode, and said second transmitter transmitting in said second mode modified frames including no payload data sequence imitati

Abstract: In order to obtain a digital radio communication receiver having a preferable frame-structure decision probability, a frame synchronization state is decided in accordance with separately detected frame-synchronization synchronous words and a frame-structure is decided in accordance with a frame-structure synchronous word and to output the frame synchronization state and the frame structure.

Abstract: A method and apparatus for reducing transmission delay in a wireless communication system that carries packetized voice and data information. Interruptions in the traffic channels cause loss of synchronization between a header compressor and a header decompressor. Rather than transmitting resynchronization information on the traffic channel, the information dropped by an interruption is re-transmitted on a non-traffic channel in parallel with the traffic channel. At the remote station, information from the traffic channel and the non-traffic channel is reassembled before input into the decompressor. Alternatively, the non-traffic channel can be used to carry overflow information so that a higher average data rate can be achieved than the average data rate of the traffic channel alone.

Abstract: A radio paging signal coding control scheme capable of improving the reception characteristic of the receiver by carrying out a coding control to determine logical channels for accommodating paging signals such that the transmission rate equivalently becomes as low as possible according to the paging signal traffic, without interrupting the paging signal coding processing while maintaining the combination of transmission rate and modulation scheme for frames, is disclosed. In the case of using prescribed transmission rate and N-valued modulation scheme, logical channels to be used for transmission of paging signals among a plurality of available logical channels are determined by setting priority orders among a plurality of available logical channels such that a number of states of modulated signals becomes less than N when paging signal traffic is small.

Abstract: An interleave frame is formed by combining slots corresponding to the same slot number in each frame when interleave process is performed in a super frame, and the data are read out along row or column direction (i.e. readout direction) and the data are written along the direction opposite to the readout direction in the same memory.

Abstract: A method and system for acquiring a time division multiplexed synchronization signal in a satellite communication system is provided. The signal is provided as a series of frames with beacon signals time division multiplexed into at least one time slot of each frame. The beacon signal in each frame comprises a unique word sequence, which is the same in each frame, and a portion of a PN sequence. The entire PN sequence is distributed into a plurality of frames forming a superframe. Initially, the power level of the incoming signal is determined by locating the maximum power received in half time slot intervals. Next a series of frames are correlated against the expected unique word, each at one of a plurality of possible frequencies. The frequency generating the maximum correlation with the unique word is selected.

Abstract: A method, system and apparatus for decreasing the time frame synchronization and resynchronization in a data communication uses an long frame sync word formed by combining a frame sync word with stuff bits, wherein the stuff bits are necessary for timing adjustments.

Abstract: A frame synchronizing signal detecting method according to the invention is used in a data multiplexing transmitter-receiver which is provided with a transmitter-receiver that transmits and receives at least a radio-frequency signal, a modulator-demodulator that converts the radio-frequency signal to a baseband signal and vice versa and a baseband signal processor that processes the baseband signal and in which the baseband signal processor is provided with a frame synchronizing signal detector, and when a frame synchronizing signal included in received data is detected, the frame synchronizing signal detector sets the detection precision of the frame synchronizing signal before a frame synchronization link is established to a value higher than regular detection precision and sets the detection precision of the frame synchronizing signal after the frame synchronization link is established to a value lower than the regular detection precision.

Abstract: A method for determining the reverse link data Rate Limit for mobile stations active on the reverse link of a High Data Rate system is disclosed. In the ideal case, the Rate Limit is based on only the number of mobile stations located in a common sector that are actually active on the reverse link. Currently, the Rate Limit is determined from the total number of mobile stations in a common sector where the total includes mobiles that are transmitting and receiving. Thus, the current method includes mobile stations that are active on the forward link and may not be active on the reverse link. In this invention, a more optimum method of estimating the reverse link loading is obtained from calculations which includes only the mobile stations which are active on the reverse link. An estimate of the reverse link loading of the mobile stations in a common cell is obtained by adding together the data rates of the data sent from each mobile in a common sector during a common frame.

Abstract: Embodiments of the present invention related generally to communication systems. One embodiment contemplates a method for operating a communication bus where the method includes detecting a start of frame symbol on the communication bus; determining a length of the start of frame symbol; detecting a start of a synchronization field on the communication bus; determining a length of an adjusted synchronization field; determining if the length of the adjusted synchronization field is less than the length of the start of frame symbol; and if the length of the adjusted synchronization field is less than the length of the start of frame symbol, concluding that the start of frame symbol is valid and concluding that the synchronization field is valid. Embodiments of the invention may be used, for example, with the Local Interconnect Network (LIN) protocol.

Abstract: A scalable pattern methodology defining positions of synchronization symbols, pilot symbols and data symbols for various numbers of sub-channels in a multi-carrier communication system. A base pattern (510) is defined identifying positions of data symbols, synchronization symbols and pilot symbols for a first number of sub-channels corresponding to a first bandwidth. The base pattern is replicated or scaled to form an expanded pattern (512, 514) identifying positions of data symbols, synchronization symbols and pilot symbols for an expanded number (M) of sub-channels corresponding to a second bandwidth. The pattern methodology may be implemented by a transmitter (100) having subdivided an original information signal into M bit streams and having encoded each of the M bit streams to 16QAM symbols to form M symbol streams, by inserting synchronization and pilot symbols into each of the M symbol streams at positions determined by the expanded pattern.

Abstract: A method for universal mobile telephone service synchronization by a mobile station operating in a GSM dedicated mode in a wireless communication system including a mobile station sending voice signals to and receiving voice signals from a base station. A voice activity detector transmits control information indicating detection of voice activity at the mobile station, and an equalizer identifies and processes a training sequence and transmitting corresponding information for the training sequence. A physical layer interface determines whether the mobile station is utilizing discontinuous transmission mode, based on the control information from the voice activity detector, and determines whether the based station is utilizing discontinuous transmission mode, based on the correlation information from the equalizer, and universal mobile telephone service synchronization is performed in response to the mobile station and the base station utilizing discontinuous transmission mode.

Abstract: A digital signal multiplexing method and apparatus in which plural degree-one multiplexed streams produced on time-divisionally multiplexing a bitstream of one or more digital signals are received and are time-divisionally multiplexed to generate a degree two multiplexed stream. Specifically, plural degree-one multiplexed streams are received, and the received degree-one multiplexed streams are time-divisionally multiplexed based on a repetitive pattern associated with the bitrate of the respective degree-one multiplexed streams to generate a degree two multiplexed stream. The time reference value attached to the degree two multiplexed stream is corrected based on the reference clocks not synchronized with the system clocks of the degree-one multiplexed streams. A pre-set volume of the dummy data is multiplexed if the corrected time reference value becomes larger than the time reference value attached to the degree-one multiplexed streams.

Abstract: A communication protocol divides the data payload (206) into segments (402, 404) with each of the payload segments (402, 404) providing a short synch word (406) which allows for an equalizer (104) to be retrained. This provides for improved performance during bursty interference conditions. The segmentation of the data also reduces the chances that the complete data in the payload has to be retransmitted due to bursty interference signals.

Abstract: The present invention provides a synchronizing data protocol comprising one or more serial input-output (SIO) control word(s) and data passed across a high voltage interface, to allow the elimination of a frame synchronization signal (and corresponding AC coupling capacitors). The present invention has particular applicability to, e.g., time division multiplexed (TDM) data, serial data communication devices, or synchronous serial communication interfaces in general, and to the communication between a controller and a codec in an audio codec device in accordance with the AC '97 Specification, i.e., the AC Link. The synchronizing data protocol is implemented over a transmit data signal line to provide occasional synchronization (i.e., not frame-by-frame synchronization) between the two communicating devices. The master device includes a preamble insertion module to insert a predetermined preamble code word into the transmitted data stream.

Abstract: A system includes a unique word correlator module which correlates a unique word field in a burst of a time division multiple access (TDMA) signal against a predefined marker sequence. Automatic timing control circuitry is coupled to the unique word correlator module. The automatic timing control circuitry derives a number of errors that are allowable during correlation of the unique word field.

Abstract: Methods and systems are provided for synchronization of a mobile terminal to a communication system which provide faster access to the communication system and reduced risk of non-productive battery power consumption. In particular, the methods and systems of the present invention test one candidate carrier from a list of candidate carriers and perform a power profile to obtain an indication of signal strength of the carrier. This signal measurement is then compared to a threshold criteria. If the criteria is satisfied, the mobile terminal attempts synchronization with that carrier and, if successful, establishes a connection with the communication system. If the criteria is not satisfied, another candidate carrier is selected and tested similarly. Furthermore, the methods and systems of the present invention provide for tiered searching for a valid carrier with each level providing an increased likelihood of finding a carrier while, potentially, requiring a greater amount of time to obtain synchronization.

Abstract: The invention relates to a method for the synchronization of at least one mobile station with a base station within a mobile telecommunication network. According to the invention, it is proposed to intensify the synchronization signal at regular intervals during a short time interval called reinforced synchronization interval or RSI interval. The cycle of activity of the synchronization channel of the base station is thus increased on a time interval corresponding to the reinforced synchronization interval. This will reduce the effective time of acquisition of the synchronization signal and thereby reduce the size or number of time windows needed for this acquisition. The cycle of activity of the synchronization channel is increased by increasing the number of synchronization bursts during the RSI interval. Application to UMTS-FDD type third-generation telecommunication networks.

Abstract: A single framer engine operates on multiple DS1 lines. The framer engines includes a memory structure for pre-aligning and storing data received from a line interface unit. The memory structure is configurable for compatibility with standard transmission formats. A recognition or comparison unit processes the pre-aligned data to determine the proper pattern sequence.

Abstract: A data synchronizing method for a radio multi-terminal communications system including a cellular telephone and a PDA (Personal Data Assistant). Messages transmitted between the cellular telephone and the PDA are prioritized. The cellular telephone and the PDA interchange the message data according to the set priority order, thereby sharing the data with reduced data processing time. A radio multi-terminal communications system is also included which uses prioritized messages for sharing data.

Abstract: The invention provides a communications system having a novel multi-frame signal format. Frequency correction information is transmitted in a time slot of a frame immediately preceding a timeslot in which synchronization information is transmitted. The invention allows faster synchronization to a cell in the communication system.

Abstract: The invention relates to a method for reducing the power consumption of a mobile station (2) connected to a packet-switched network (4), in which packet-switched network information is sent in the form of data frames. In the method, a paging period is specified for the mobile station for sending paging messages (UD1) essentially at the intervals of said paging period to the mobile station, the mobile station (2) is set to the standby mode at least for the time of the reception of the paging messages (UD1), and the mobile station, which is in the standby mode, is set to the idle mode after the reception of the paging message (UD1). In the idle mode, some of the functions of the mobile station (2) are set to the power saving mode or switched off.

Abstract: A method and apparatus for synchronizing to a time structure associated with base station transmissions in a radiocommunication system are described. A broadcast control channel can contain synchronization symbols within one or more of a plurality of timeslots. The symbols can be provided as periodic, e.g., exponential, signals which introduce a frequency deviation into the broadcast control channel. This frequency deviation can be recognized by the receiver to synchronize to the time structure of the base station transmissions. Moreover, the variation in the frequency deviation caused by phase rotation associated with local oscillator inaccuracy can also be compensated to achieve frequency synchronization.

Abstract: An audio decoder architecture makes use of various component sharing techniques to conserve hardware and reduce implementation cost. In one embodiment, the audio decoder comprises a bitstreamer, a synchronization controller, a first and second decode controllers, a memory module, a data path, and an output buffer. The bitstreamer retrieves compressed data and provides token-aligned data to the synchronization controller and decode controllers. The synchronization controller initially controls the bitstreamer to locate and parse audio frame headers to extract decoding parameters. The synchronization controller initiates the decode controller which corresponds to an identified compression format, and turns control of the bitstreamer and data path over to the selected decode controller. The selected decode controller then controls the bitstreamer to parse the variable length code compressed transform coefficients.

Abstract: A method of carrying out multiplex transmission of a subscriber service signal, includes the steps of (a) converting a subscriber service signal including x digital subscriber line (xDSL) signals, from an analog form to a digital form, (b) storing a plurality of thus converted sampling digital signals and control signals into a first multiple signal, and multiplexing in time-sharing a plurality of the thus produced first multiple signals to thereby produce a second multiple signal, and (c) transmitting the second multiple signal.

Abstract: For a method for searching synchronization patterns in serial, packet-oriented and multiplexed data streams, the m bits of a synchronization pattern are continuously inserted into each nth packet of a data stream. One bit of bits of the serial data stream that is acquired and comprises n packets is respectively stored in a memory cell of allocated memories that are m memory cells wide, said memory cell representing a bit position within n packets. The number of memories is determined by n×number of bits per packet. Upon recognition of a bit pattern in one of the memories, the bit position of the bit pattern in the serial data stream is defined.

Abstract: The present invention provides a method of generating a data stream comprising: generating a first slot having a first data field; generating a second slot; and providing the second slot within the first data field of the first slot. The present invention additionally provides methods of validating an integrated circuit and communicating a data stream.

Abstract: Methods and systems are provided for synchronization of a mobile terminal to a communication system which provide faster access to the communication system and reduced risk of non-productive battery power consumption. In particular, the methods and systems of the present invention test one candidate carrier from a list of candidate carriers and perform a power profile to obtain an indication of signal strength of the carrier. This signal measurement is then compared to a threshold criteria. If the criteria is satisfied, the mobile terminal attempts synchronization with that carrier and, if successful, establishes a connection with the communication system. If the criteria is not satisfied, another candidate carrier is selected and tested similarly. Furthermore, the methods and systems of the present invention provide for tiered searching for a valid carrier with each level providing an increased likelihood of finding a carrier while, potentially, requiring a greater amount of time to obtain synchronization.

Abstract: An air frame synchronisation signal is transmitted as a data signal over a PCM link from a central unit to a plurality of remote radio transceivers, allowing the remote radio transceivers to recreate the AFS signal with the desired accuracy, compensating for transmission delays.

Abstract: According to the present invention a system and a method for synchronising digital communication systems is proposed. Thereby a reference symbol RS consisting of a sequence of a plurality of synchronisation patterns SP and followed by data symbols, which are both modulated (13) on a RF-frequency is provided. The received reference symbol (RS) is correlated with a delayed version of itself and the correlation peak is identified giving the position and complex correlation result that can be used for the timing and frequency synchronisation of a digital communication system. According to the present invention the phase of the last and/or the first of the plurality of synchronisation patterns SP of said reference symbol RS (or a part or a multiple thereof) is phase shifted, e.g. by 180.degree., before the transmission step.

Abstract: A combination of one or more HMG-CoA reductase inhibitors (for example pravastatin, lovastatin, simvastatin, fluvastatin, rivastatin or atorvastatin) with one or more insulin sensitizers (for example troglitazone, pioglitazone, englitazone, BRL-49653, 5-(4-{2-[1-(4-2'-pyridylphenyl)ethylideneaminooxy]ethoxy}benzyl)thiazolidi ne-2,4-dione, 5-{4-(5-methoxy-3-methylimidazo[5,4-b]pyridin-2-ylmethoxy)benzyl}thiazolid ine-2,4-dione or its hydrochloride, 5-[4-(6-methoxy-1-methylbenzimidazol-2-ylmethoxy)benzyl]thiazolidine-2,4-d ione, 5-[4-(1-methylbenzimidazol-2-ylmethoxy)benzyl]thiazolidine-2,4-dione and 5-[4-(5-hydroxy-1,4,6,7-tetramethylbenzimidazol-2-ylmethoxy)benzyl]thiazol idine-2,4-dione) exhibits a synergistic effect and is significantly better at preventing and/or treating arteriosclerosis and/or xanthoma than is either of the components of the combination alone.

Abstract: A device and method for synchronizing a series of data packets in a bitstream using a histogram which accumulates a count of occurrences of a particular synchronization pattern at a given location in each packet and identifies the start of a data packet based on the count of such occurrences stored in the histogram.

Abstract: A mobile communication system transmitting data in frame unit includes a base station apparatus and a terminal apparatus. The transmitter has a controller having consecutive first and second frames each divided into a first interval and a second interval following the first interval. In a handoff mode, the controller transmits respective frame data in the first interval of the first frame and the second interval of the second frame and stops transmission of the data in the second interval of the first frame and the first interval of the second frame. Further, the terminal apparatus (i.e.

Abstract: A method and apparatus for synchronizing and demodulating radio wave signals transmitted in frame format with an unique word, involving correcting the frequency offset of the received signal and differentially correlating the frequency corrected signal with the unique word, A first timing estimate is further refined by a 2-D search between frequency and time and a first frequency estimate is further refined by quadratic interpolation. The finely synchronized signal is demodulated using a Viterbi-based demodulator.

Abstract: A method for synchronizing a cycle master node to a cycle slave node, including the steps of utilizing logic circuitry in the cycle slave node to determine a timer offset value, in response to the cycle slave node receiving synchronization information, transmitting the timer offset value to the cycle master node, and, utilizing logic circuitry in the cycle master node to adjust a value of a cycle master node cycle timer on the basis of the timer offset value. The synchronization information is preferably a cycle reset signal that is asserted at a prescribed rate which is a multiple of one cycle of the cycle slave node cycle timer. The cycle master node and the cycle slave node can advantageously be included in a first network or sub-network and the cycle reset signal can be supplied by a second network or sub-network which is external to the first network or sub-network.

Abstract: New methods for synchronizing previously unsynchronized BTS's of time division multiple access cellular networks are disclosed. Timing information that is readily available throughout the network is used to determine for each BTS when information representing a particular event is transmitted relative to the timing information. The time differences that are detected are used for steering the clock of each BTS to have the next or some other subsequent event transmitted at the same time.

Abstract: In a method and apparatus for detecting a wake packet among data bytes in a packet frame issued by a network device, the data bytes in the packet frame are initially compared with a sync byte to detect start of a synchronization stream of the wake packet. The number of consecutive sync matches of the data bytes in the packet frame with the sync byte is counted, and a partial match flag is set upon detection that the number of consecutive sync matches has reached a predetermined number of sync duplications of the sync byte to indicate that the synchronization stream has been detected in the packet frame. When the partial match flag is set, the data bytes that follow the synchronization stream in the packet frame are compared with address bytes of a destination address assigned to a sleeping node.

Abstract: A network interface in a workstation computer includes a pattern matching circuit to enable the workstation computer to wake up to perform prescribed operations requested by a remote workstation. The pattern recognition circuit includes a pattern memory configured for storing a pattern entry for at least a portion of a predetermined pattern. The pattern entry includes a pattern data field and a second field specifying a number of bytes in the input data stream to be ignored prior to comparison with the pattern data field. The pattern matching circuit also includes a comparator for comparing the pattern data field with a selected group of bytes from the data stream. Pattern match logic determines whether the received data packet includes the predetermined pattern based on the comparison result.

Abstract: A DAB receiver, an apparatus and a method for converting a first sequence of data having a fixed frame structure, wherein locations within the frame are reserved for predetermined data types, into a second sequence of data, having a different frame structure. The data belonging to the respective data types are grouped in separate sequences with a frame type identifier attached to the sequences for identifying the different sequences. This allows an easy identification of the different sequences of data within the second sequence without the need of prior knowledge of the exact location of the sequences within the second sequence. An example of such a conversion is the conversion of the channel decoder output of a DAB receiver into a format suitable for embedding in the IEC958 format.

Abstract: The amount of jitter that results in a serial receiver having a parallel architecture Can is reduced by insuring that the edges specifically introduced by the code are actually received by the phase detector. In particular, the code is designed to increase the probability that the edges it introduces are actually received by the phase detector. In a preferred embodiment of the invention, all the edges introduced by the code are actually received by the phase detector. This is achieved by guaranteeing that the edges introduced by the code are evenly spaced in the data stream at a rate corresponding to the phase detector sampling rate. For example, if the receiver consists of N data samplers, e.g., N=5, and one phase detector, the edges introduced by the code are arranged to be N symbols apart. This may be done by inserting as the Nth symbol an overall symbol that has a dummy component so that an edge results between the N-1 symbol and the overall Nth symbol.

Abstract: Each frame of a pilot channel transmission in a spread spectrum communications system is divided into a plurality of synchronization slots. Each of the synchronization slots includes a pilot code, and at least one of the synchronization slots further includes a framing synchronization code. To extract frame and slot synchronization information from the pilot channel transmission, pilot code timing is first identified by applying a matched filter or correlation to a received pilot signal, identifying peaks, and using the peaks to find a timing reference indicative of synchronization slot boundaries. Next, the set of known framing synchronization codes are correlated with the received signal over the included found synchronization slots. Given that the location within the frame of the known framing synchronization code(s) is known, once a correlation match is found at a certain slot location, the boundary of the frame (i.e., the frame synchronization) relative thereto is then also known.

Abstract: To test the processing of a data frame processing unit (FPU) which, in a normal working mode, processes input data frames applied to a data frame input (FI) thereof, the data frame processing unit (FPU) is brought in a test mode. Therefore, an active test signal is applied to a test mode control input (TCI) of this data frame processing unit (FPU). When brought in the test mode, the frame counters of the data frame processing unit (FPU) have lower limits and test data frames with smaller dimensions than the input data frames applied to the data frame input (FI).

Abstract: A circuit and method for framing an input data stream to a periodic signal. The circuit comprises a register circuit, a logic circuit and a multiplexor circuit. The register circuit may be configured to store information and to present a first and second output in response to (i) the input data stream and (ii) the periodic signal. The logic circuit may be configured to (i) detect a predetermined bit sequence and (ii) present a control signal in response to the information stored in the register circuit. The multiplexor circuit may be configured to present one or more multiplexed signals comprising the first and second outputs of the register circuit in response to the control signal.

Abstract: A system and method for scheduling temporal data and non-temporal data to create a unified stream of data that includes both the temporal and non-temporal data and for processing the unified data stream. The temporal and non-temporal data is preferably in a compressed format. The system preferably includes a scheduler that takes temporal data (e.g., sound data) and non-temporal data (e.g., image data) and interleaves them together to form the unified data stream. The system also includes a processor that decompresses the compressed image data and produces an output image from both the decompressed image data and any uncompressed image data. The processor also plays the temporal data while it concurrently decompresses the compressed temporal data. The system can handle temporal data in any format, including voice data and MIDI files, as well as any type of image data, including videos and still images.

Abstract: A TR-8 compatible Remote Terminal (RT) with 96 subscriber line capacity is partially or wholly replaced with one or more D4 channel banks each comprising 24 subscriber line capacity without changing the TR-8 interface module within the servicing telecommunications exchange. The D4 channel bank is connected via a T-1 digital link to any one of the A, B, C, and D links within the TR-8 interface module. A-B bit pattern data and time slot assignments communicated between the D4 channel bank and the TR-8 interface module are converted to be compatible with each other. If a D4 channel bank is connected to the TR-8 interface module via an A-link, the maintenance data are further ignored. Connecting a D4 channel bank to a TR-8 interface module allows small telecommunications service providers to more economically provide line access to sparsely populated customer sites.

Abstract: A continuous synchronization adjustment algorithm is described, which continuously synchronizes frames used in digital synchronous transmissions. By letting the receiver continuously adjust the assumed frame position, rather than adjusting only once per frame as conventionally done, a significant increase in bit error rate can be achieved. When an incorrect single sync bit is detected in a frame, thereafter during the rest of the frame, the single sync bit positions that would result from an advance or delay of the frame position (e.g., due to a bit slip in the frame) are checked. The frame position is then adjusted immediately, without waiting for the beginning of the next frame. Consequently, there is a significant decrease in the number of data bits that are interpreted incorrectly or disregarded. As such, the bit error rate resulting from the present continuous algorithm is significantly improved over that resulting from prior synchronization algorithms.

Abstract: A method is provided for detecting a synchronization word in frames of serially transmitted data. The synchronization word consists of l synchronization bits, which are transmitted one bit per frame at a known position in each frame. The method comprises the steps of: storing each incoming bit in a memory organized as groups of words, each having at least l bits, so that each group of words contains bits from a same position in consecutive frames; rotating each group of words; comparing the group of words, at each rotation, to the synchronization word.

Abstract: A variable rate transmission method that can vary the transmission rate of data. A transmitting side supplies a transmitted data sequence to an error detecting encoder 105 and a frame memory 103. The frame memory 103 stores data of a variable length to be transmitted in one frame. The error detecting encoder 105 calculates an error detecting code (such as CRC code) for each frame of the transmitted data. A multiplexer 104 adds the calculated error detecting code ahead of the transmitted data to place it at the initial position of the frame, and sequentially outputs the data sequence frame by frame. A receiving side calculates an error detecting code of the data in each transmitted frame in the same manner as the transmitting side, and compares the calculated error detecting code with the error detecting code at the initial position of the frame. The end bit of the frame data is decided as a position at which the two error detecting codes coincide.

Abstract: A synchronization method and apparatus for synchronizing a receiver, such as a radiotelephone operable in a cellular communication system with a transmitter. Synchronization signals are transmitted as parts of a control signal to the receiver. Such synchronization signals are of high margins and also permit synchronization of the radiotelephone responsive to a reduced number of calculations. The time for such synchronization is reduced by use of nonlinear transformation metrics, such as logarithmic metrics, which reduce the impact of a noise or error component within the control signal.