Abstract: A system and method for transmitting wideband signals via a radio communication system adapted for transmitting narrow-band signals is described. A base station is used to transmit and receive a plurality of relatively narrow-band and a plurality of relatively wideband signals. The electromagnetic spectrum available to the plurality of narrow-band signals is selectively shared with the electromagnetic spectrum available to the wideband signals by systematically separating the orthogonal codes and the carrier frequencies used for transmission. The prefixes of the orthogonal codes are preferably mutually exclusive and the carrier frequencies are preferably separated by an offset. The offset may be substantially equal to an integer multiple of the narrow-band signal's chip rate. Alternatively, the offset may be substantially equal to an odd multiple of one half the narrow-band signal's chip rate in which case every other bit of the orthogonally encoded data is inverted.

Abstract: An apparatus for use with a shared access communication channel is disclosed. The chipping rate of a first group of terminals is determined. Transmissions on the shared access communication channel are encoded using first pseudorandom noise (PN) code and a phase shift at the first chipping rate and an orthogonal spreading code having a chipping rate less than the first chipping rate. The apparatus may receive a feedback channel assignment and may receive an indication of a change in timing on the assigned feedback channel.

Abstract: Disclosed are an apparatus and a method for generating a preamble signal for cell identification in an OFDM mobile communication system. The method includes the steps of generating a Walsh code symbol for a cell identification by combining Walsh codewords having a predetermined length and generating the preamble signal through multiplying the Walsh code symbol by a pseudo noise (PN) code having a length identical to a length of the Walsh code symbol.

Abstract: A system and method for adaptively controlling feedback information according to a loading condition of a communications cell is provided. A method comprises receiving an indication from a base station, computing an amount of feedback information to transmit back to the base station using the indication, locating a feedback resource assigned to the mobile station using the amount of feedback information and an identity of the mobile station, computing a feedback information, and transmitting the feedback information using the located feedback resource. The indication is for a set of candidate transmission formats that is based on loading conditions in the cell.

Abstract: It is desired to suitably carry out transmission processing and reception processing carried out when transmitting a multicarrier signal where specific subcarriers are omitted. Therefore, the present invention carries out transmission avoidance processing operable when transmitting a multicarrier signal to replace signals corresponding to subcarriers, in a plurality of subcarriers, at frequency positions where transmission is avoided with a null signal. Subsequently, an inverse Fourier transform is carried out on the output of the transmission avoidance processing, the transmission power of the multicarrier signal that has been transformed is amplified in accordance with the number of subcarriers replaced with the null signal and the multicarrier signal is transmitted.

Abstract: Systems and methods for maintaining synchronization of a base unit and a portable unit in a low-power mode are provided. The base unit and the portable unit communicate with each other via wireless frequency hopping radio communications links. The base unit and the portable unit switch to a synchronization state in a synchronization period during the low-power mode. During the synchronization period, the base unit transmits one of a first and a second link synchronization messages. The portable unit is required to respond to the second link synchronization. If the base unit receives a response from the portable unit within a predetermined number of periods, the base unit and the portable unit switch back to the low-power mode. Otherwise, the base unit and the portable unit are switched to a SEARCH state to search for a synchronized communications channel.

Abstract: One embodiment of the invention provides a method of creating a set of secondary spreading codes for use in a satellite navigation system comprising a constellation of satellites. Each satellite in the constellation employs a tiered spreading code comprising at least a primary code and a secondary code. Each satellite in the constellation is allocated a different secondary spreading code from the set of secondary spreading codes. The method involves generating an initial set of bit patterns, where each bit pattern represents a potential secondary spreading code. The method further involves performing an optimisation process on bit patterns within the initial set of bit patterns. As a result of the optimisation, at least some of the bit patterns in the initial set are modified or replaced, to create a final set of bit patterns for use as the set of secondary spreading codes.

Abstract: A method of transmitting signals from electronic housings, each mounted on one wheel of a vehicle, to a central unit (11) on the vehicle, uses spread spectrum. There is allocated, on the one hand, to each electronic housing (6-9) and to the central unit (11), a first common generic orthogonal spread code (Cg) identical for the electronic housings and the central unit and, on the other hand, to each electronic housing, a second orthogonal spread code (Ci) specific to the electronic housing. An initializing procedure causes the transmission by each electronic housing of a spread signal (e) based on the common generic spread code (Cg), incorporating the second specific orthogonal spread code (Ci) and the identification code (ID) of the electronic housing. Subsequent transmissions include transmission by each electronic housing of a spread signal (e) on the basis of the second specific spread code (Ci) of the electronic housing.

Abstract: A transmitter includes: spread code multiplying means that multiplies a symbol indicating a reference signal by spread code to generate a chip sequence after spreading; chip pattern generation means that generates a chip pattern by performing chip repetition a predetermined repetition number of times on the chip sequence after spreading; and multiplying means that multiplies a signal having the chip pattern by a phase specific to the transmitter.

Abstract: Embodiments of the disclosure provide methods, apparatus, and articles allowing two nodes to communicate in a slot-based direct sequencing spreading communication system. Both a preamble sequence and a payload data spreading PN sequence are generated from the Time of Day and a given user code. Generated sequences are synchronized between two communicating nodes to allow slot-based DSSS communication to take place. Generated sequences also change dynamically from slot to slot to provide waveform security.

Abstract: A method and system for defining additional spread spectrum channels within a coverage area already served by an existing wireless network. A first spread spectrum channel may be defined by a first range of frequencies. A second spread spectrum channel may be defined by a second range of frequencies. A portion of the first range of frequencies may overlap with a portion of the second range of frequencies. The overlap may be such that the first spread spectrum channel and the second spread spectrum channel may carry signals that minimally interfere with each other.

Abstract: A communication technique based on direct sequence spread spectrum signaling employs, for all users sharing an access channel, a single spreading code that has a duration sufficiently longer than the symbol length that the likelihood of confusion between users is minimized if not eliminated. The length of the spreading code is sufficiently long that contention events can occur only when two bursts occur at the receiver within one chip time of one another.

Abstract: A disclosed code-division-multiple-access (CDMA) system has a base station (BS) and remote stations (RSs). A BS-spread-spectrum transmitter broadcasts a common-synchronization channel having a chip-sequence signal common to the remote stations served by the BS, and a frame-timing signal. A RS-spread-spectrum receiver receives the broadcast common-synchronization channel, and determines frame timing from the frame-timing signal. A first RS-spread-spectrum transmitter transmits an access-burst signal, which has a plurality of segments. Each access burst signal segment has a plurality of power levels. A BS-spread-spectrum receiver receives the access-burst signal at a detected-power level. In response to receiving the access-burst signal, a BS-spread-spectrum transmitter transmits an acknowledgment signal to the RS-spread-spectrum receiver.

Abstract: A radio communication system having a radio transmitter and a radio receiver and adopting multiple carrier modulation and code spreading modulation methods is disclosed. The radio communication system comprises a selecting unit provided in the radio transmitter or the radio receiver, for selecting an interleaving mode out of plural interleaving modes depending on radio propagation path conditions; a symbol configuration unit provided in the radio transmitter; and a symbol reconfiguration unit provided in the radio receiver. The symbol configuration unit configures information symbols to be transmitted by the radio transmitter in both time and frequency directions in a pattern according to the interleaving mode selected by the selecting unit, and the symbol reconfiguration unit reconfigures information symbols received by the radio receiver in both time and frequency directions in an inverse pattern of the pattern.

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 system (10) for communicating a direct sequence spread spectrum signal, a related transmitter (12), a related receiver (14), and methods associated therewith are provided in various embodiments. A data rate vector, a processing gain vector, a frequency separation vector, and a bit energy vector may be associated with transmitting and/or receiving a direct sequence spread spectrum signal. Each vector has a value associated with each of a plurality of channels associated with subcarriers in the direct sequence spread spectrum signal. A value for at least one of the data rate vector, processing gain vector, frequency separation vector, and bit energy vector for at least one channel is different from another value for the corresponding data rate vector, processing gain vector, frequency separation vector, or bit energy vector for another channel.

Abstract: The number of users and data capacity of wireless systems are increased by employing apparatus and method for increasing the number of spreading codes available in the system by providing a mechanism to reuse the already allocated spreading code or use the codes that may correlate to those already being used within the same sector/cell. This, in return, provides capacity improvement proportional to the number of added base station (BS) antennas for each cell. An antenna null steering technique for code allocation maintains the cross correlation properties of the codes only for the desired user and to obtain a gain in capacity improvement.

Abstract: A spread spectrum communications system using long, scalable PN sequences to achieve variable communication rates using a low-complexity and scalable matched filter architecture to provide a large processing gain, robust recovery of multiple devices in long reach, high ambient-noise environments.

Abstract: A method for maintaining the quality of transmission from a head end to a service unit in a telecommunications system that uses a multi-carrier transmission scheme with dynamic bandwidth allocation is disclosed. The method involves allocating a first payload channel to a service unit in a subband of a transmission channel of the telecommunications system and monitoring the quality of the first payload channel. When the quality of the first payload channel drops below a threshold, the method allocates a second, different payload channel to the channel unit.

Abstract: Disclosed are apparatus that implement blind selected mapping techniques that provide for crest factor reduction of forward link CDMA signals. Communication signals are processed using a mathematical algorithm that selectively maps a summed communication signal in a frame to another summed communication signal which has a smaller peak-to-average power ratio. The reduced dynamic range communication signal is amplified and transmitted to a receiver. At the receiver, the reduced power communication signal is processed using a mathematical algorithm that detects the selected mapping index used in the transmitter and converts the received signals into the original communication signals.

Abstract: Carrier Interferometry (CI) provides wideband transmission protocols with frequency-band selectivity to improve interference rejection, reduce multipath fading, and enable operation across non-continuous frequency bands. Direct-sequence protocols, such as DS-CDMA, are provided with CI to greatly improve performance and reduce transceiver complexity. CI introduces families of orthogonal polyphase codes that can be used for channel coding, spreading, and/or multiple access. Unlike conventional DS-CDMA, CI coding is not necessary for energy spreading because a set of CI carriers has an inherently wide aggregate bandwidth. Instead, CI codes are used for channelization, energy smoothing in the frequency domain, and interference suppression. CI-based ultra-wideband protocols are implemented via frequency-domain processing to reduce synchronization problems, transceiver complexity, and poor multipath performance of conventional ultra-wideband systems.

Abstract: A radio communication system having a radio transmitter and a radio receiver and adopting multiple carrier modulation and code spreading modulation methods is disclosed. The radio communication system comprises a selecting unit provided in the radio transmitter or the radio receiver, for selecting an interleaving mode out of plural interleaving modes depending on radio propagation path conditions; a symbol configuration unit provided in the radio transmitter; and a symbol reconfiguration unit provided in the radio receiver. The symbol configuration unit configures information symbols to be transmitted by the radio transmitter in both time and frequency directions in a pattern according to the interleaving mode selected by the selecting unit, and the symbol reconfiguration unit reconfigures information symbols received by the radio receiver in both time and frequency directions in an inverse pattern of the pattern.

Abstract: A CDMA communication system includes a signal processor which encodes voice and nonvoice signals into data at various rates, e.g. data rates of 8 kbps, 16 kbps, 32 kbps, or 64 kbps as I and Q signals. The signal processor selects a specific data rate depending upon the type of signal, or in response to a set data rate. When the signal is received and demodulated, the baseband signal is at the chip level. Both the I and Q components of the signal are despread using the conjugate of the pn sequence used during spreading, returning the signal to the symbol level. Carrier offset correction is performed at the symbol level. A lower overall processing speed is therefore required.

Abstract: The present invention relates to a spreading signal assigning method and a signal transmitting method in a direct sequence CDMA mobile communication system, a mobile wireless communication system using the methods, and a transmitter, a receiver and a transceiver in the mobile wireless communication system in which an assignment method of a second spreading code is devised such that various services can be provided. The invention is configured such that a signal spread with the second spreading code is transmitted between a base station and a mobile station by assigning a code associated with each base station group or a code associated with each network type to which the base station group belongs as the second spreading code.

Abstract: A method for applying one or more code values to an input signal value to produce an output signal value in a CDMA communications scheme, wherein the code value or values may lie only either on or equally distant from an orthogonal pair of axes defining a two dimensional signal space, the input and output signal values each have components along each axis and the method comprises processing, via a logic function, the code value or values to produce two multiplier values and a selector value, creating two product values by multiplying the multiplier values with respective components of the input signal value, negating one of the product values to produce a third product value and selecting, on the basis of the selector signal, two of the three product values to become the components of the output signal value.

Abstract: Communication circuitry uses a combination of Pseudo-Noise (PN) coded and non-PN coded transmission periods to represent different data values. In one embodiment, a number of data values are encoded into a smaller second number of encoded ternary values. The Pseudo-Noise (PN) codes are transmitted representing some of the encoded ternary values and no transmitted PN codes represent other encoded ternary values. The throughput of spread spectrum radio systems is increased by representing data values in fewer spread spectrum time slots.

Abstract: An ultra-wideband (UWB) transceiver for use in UWB communication includes a voltage-controlled oscillator (VCO) configured to periodically and sequentially generate a series of base frequencies based on a predetermined sequence and a waveform generator to generate carrier waves based on the generated base frequencies.

Abstract: A method of encoding identity of events comprises: receiving an event bit pattern having bits representative of events, and determining a code from the event bit pattern, said code containing the information for recovering identity of events when one or more events are simultaneously present in the event bit pattern.

Abstract: Provided are a pulse signal generator for UWB radio transception and a radio transceiver having the same. The pulse signal generator includes: an envelope generator generating a plurality of envelope signals; a local oscillator array composed of a plurality of high frequency oscillators, each outputting two oscillation signals having a phase difference from each other; a multiplier array receiving the envelope signals and the oscillation signals and outputting signals obtained by respectively multiplying the envelope signals by the oscillation signals; and an I channel adder and a Q channel adder outputting an I channel pulse signal and a Q channel pulse signal by adding output signals having the same phase components among the signals output from the multiplier array, respectively.

Abstract: A disclosed code-division-multiple-access (CDMA) system has a base station (BS) and remote stations (RSs). A BS-spread-spectrum transmitter broadcasts a common-synchronization channel having a chip-sequence signal common to the remote stations served by the BS, and a frame-timing signal. A RS-spread-spectrum receiver receives the broadcast common-synchronization channel, and determines frame timing from the frame-timing signal. A first RS-spread-spectrum transmitter transmits an access-burst signal, which has a plurality of segments. Each access burst signal segment has a plurality of power levels. A BS-spread-spectrum receiver receives the access-burst signal at a detected-power level. In response to receiving the access-burst signal, a BS-spread-spectrum transmitter transmits an acknowledgment signal to the RS-spread-spectrum receiver.

Abstract: A direct sequence spread spectrum (DSSS) transceiver including a DSSS transmitter and a DSSS receiver, wherein the DSSS transmitter includes: an integral code mapping unit mapping source bit data in one of 2N (N is a natural number) of predetermined symbols by N bits and mapping the symbol in one of integral code words that are obtained by previously integrating each of 2N of bi-orthogonal code words; and a radio frequency (RF) transmitting unit transmitting the integral code words mapped by the integral code mapping unit over an RF carrier wave, and the DSSS receiver includes: an RF receiving unit removing an RF carrier wave from an RF signal from the RF transmitting unit and converting an analog signal obtained by removing the RF carrier wave from the RF signal into a digital signal; a differential circuit unit differentiating and converting the digital signal from the RF receiving unit into bi-orthogonal code words; and a symbol detection unit detecting a symbol corresponding to a maximum value of correlat

Abstract: A method and apparatus for reducing peak transmitter power includes providing a set of orthogonal communication codes for a telecommunications system that includes a set of active user codes and a set of inactive user codes (1404). A communication signal is generated from the set of active user codes (1406). The peak-to-average power ratio of the communication signal is reduced by performing a peak cancellation function on the communication signal that minimizes energy distribution at least one of the set of active user codes and the set of inactive user codes (1410).

Abstract: A method and system for acquiring beamforming vectors using multiple spreading sequence spreading gains is disclosed. One embodiment of the invention allows time and power to be saved by spreading a training sequence with spreading sequences of different gains in different iterations of an iterative beamforming acquisition procedure.

Abstract: Encoded digital symbols are transmitted via a first pair of antennas and at least one second pair of antennas. The sets of symbols used for the transmission via the second pair of antennas are re-ordered temporally into subsets of symbols with respect to the symbols used for the first pair of antennas. For the first pair of antennas, there is used a signal subjected to encoding with a code-division-multiple-access code and subjected to spreading with a spreading code, and, likewise, for the second pair or pairs of antennas there are used signals subjected to encoding with respective code-division-multiple-access code and subjected to spreading with a respective spreading code. At least one between the respective code-division-multiple-access code and the respective spreading code used for the transmission via the second pair of antennas is different from the code-division-multiple-access code and from the spreading code used for the transmission via the first pair of antennas.

Abstract: First normalizing means (12) normalizes first and second code streams (s1, s2). First spreading means (13) spreads the output of the first normalizing means (12). STTD coding means (14) subjects the first and second code streams (s1, S2) to STTD coding. Second normalizing means (15) normalizes the output of the STTD coding means (14). Second spreading means (16) spreads the output of the second normalizing means (15) by means of the same spreading code as that of the first normalizing means (12). Orthogonal transforming means (17) gives the negative signs to odd chips in a second path spread sequence of each code and exchanges the orders of the odd and even chips. Combining means (18) adds first and second spread sequences of the second path produced by orthogonally transforming the first and second spread sequences of the first path. With this, by using the orthogonality of the transmitted sequences at the receiving side, the reception signal can be detected with a lower complexity.

Abstract: Systems for multipoint-to-point communication using orthogonal frequency division multiplexing and identification codes are provided. In one embodiment, a system comprises: a host unit; and a plurality of remote units using a multiple access scheme to communicate at the same time with the host unit using orthogonal frequency division multiplexing (OFDM); wherein the host unit allocates orthogonal tones within the system to the plurality of remote units; wherein the host unit sends an adjustment signal to at least one of the remote units instructing the at least one remote unit to adjust the timing of transmissions from the remote unit to improve orthogonality of an OFDM waveform received at the host unit, and wherein the host unit associates an address code with each of the plurality of remote units for designating downstream signals to the remote units.

Abstract: Apparatus and systems, as well as methods and articles, may operate to detect radio-frequency energy at a frequency associated with at least one wireless networking channel and to transmit a data frame responsive to determining that the radio-frequency energy is not associated with a wireless networking transmission.

Abstract: System and method for detecting multiple direct sequence spread spectrum signals using a multi-mode searcher. A preferred embodiment comprises the specification of a hypothesis for a particular communications network. The hypothesis can then be used to generate a pseudo-random number (PN) sequence that is provided to a searcher. The searcher can then make adjustments to the PN sequence to bring the PN sequence to conformity with requirements of the particular communications network. The adjustment to the PN sequence permits the use of a multi-mode searcher to perform searches for signals of various communications networks with minimal hardware dedicated to each communications network.

Abstract: In a transmitter, an upconverter converts a lower frequency signal to a higher frequency signal. Prior to the upconversion, a compensator compensates for at least gain/phase distortion that will be introduced into the lower frequency signal by at least the upconverter.

Abstract: The punctured pilot channel comprises information symbols of uncertain sign punctured into a sequence of pilot channel symbols of predetermined sign. The apparatus includes an information sign demodulation circuit for determining the sign of the information symbols in response to the pilot channel symbols. A continuous pilot generator generates a non-punctured pilot channel of predetermined sign from the information symbols and the pilot channel symbols. In a first embodiment, the information sign demodulator further comprises a dot product circuit for calculating a dot product of the pilot channel symbols and the punctured information symbols, and a threshold comparator for comparing the dot product to a predetermined threshold.

Abstract: A system and method for transmitting data from a satellite to a terrestrial receiving station are provided. The system comprises a satellite including a rate adaptive data receiver. The system is configured to establish a data transmission for the satellite to the terrestrial receiving station; the data transmission having an initial transmission rate. The system further monitors one or more downlink parameters of the data transmission, and when the one or more downlink parameters meets a criteria, both the rate adaptive data transmitter and the rate adaptive data receiver simultaneously adjust the data transmission to a new data transmission rate, and transmit the data at the new data transmission rate.

Abstract: A wireless communication system (10). The system comprises a user station (12). The user station comprises despreading circuitry (22) for receiving and despreading a plurality of slots received from at least a first transmit antenna (A121) and a second transmit antenna (A122) at a transmitting station (14). Each of the plurality of slots comprises a first channel (DPCH) comprising a first set of pilot symbols and a second channel (PCCPCH) comprising a second set of pilot symbols. The user station further comprises circuitry (50) for measuring a first channel measurement (?1,n) for each given slot in the plurality of slots from the first transmit antenna and in response to the first set of pilot symbols in the given slot. The user station further comprises circuitry (50) for measuring a second channel measurement (?2,n) for each given slot in the plurality of slots from the second transmit antenna and in response to the first set of pilot symbols in the given slot.

Abstract: Data is estimated of a plurality of received spread spectrum signals. The plurality of received communications are received in a shared spectrum. The received communications are sampled to produce a received vector. The received vector is processed to produce a plurality of segments. Each segment is processed separately to estimate data of the received communications.

Abstract: A satellite broadcasts radio programs to mobile and fixed receivers at various locations. Ground stations supplement the satellite broadcasts in areas where the satellite signal may be shadowed. Likewise, the satellite signal supplements the terrestrial transmissions in areas with marginal terrestrial signal strength. Ground stations and a satellite transmit the same digital symbol stream over a same frequency spectrum. The symbol streams arrive in each service area of the ground stations with a relative delay that is within a window for which a receiver is adapted to decode efficiently. Spectral efficiency is achieved by allowing the ground stations to share the same frequencies as the satellites.

Abstract: A parametric form of G-Rake and chip equalization for closed-loop transmit diversity is provided, that accounts for impairment correlation between transmit antennas. In a closed-loop transmit diversity system, the base station transmits a signal from two or more antennas, using one of a predetermined set of relative phase offsets at one of the antennas. The parametric estimation of the impairment or data covariance is performed by summing terms, including a term for each possible phase offset. The terms are weighted by fitting parameters. The fitting parameters are jointly solved by fitting the impairment or data covariance estimate to a measured impairment or data covariance. In another aspect, a measured impairment covariance is formed by exploiting a special relationship between the pilot channels of the different transmit antennas.

Abstract: A transmission signal generating circuit in a radio base station that employs spread processing circuits in order to output spread transmission signals. The signal generating circuit further contains power class selecting circuits, which categorize spread transmission signals into power classes, a first adding circuit, which combines these signals, multipliers, which adjust transmission power of these signals for respective power classes, and a second adding circuit, which combines these signals. The circuit measures and quantinizes the total transmission power to output a power level. A power limitation control memory outputs a multiplication coefficient representing the power class for which transmission power control. Selectors in the circuit select when this control is permitted for a given power class and output this information to the multiplier corresponding to the class.

Abstract: Data is transferred in a wireless communication system, such as a wireless spread spectrum communication system. A plurality of transmitting antennas are provided. Data is encoded to produce a plurality of data streams for each of the plurality of codes. The plurality of data streams are spread with the plurality of spreading codes, and for each transmitting antenna, one of the spread data streams of each code together is combined to produce a spread data vector. Each transmitting antenna transmits its spread data vector. The transmitted spread data vectors are received by each of a plurality of receiving antennas as a received version, and the data is recovered using the received versions.

Abstract: The invention relates to a method for controlling the weighting of a data signal in the at least two antenna elements of a multi-element transceiver 1 of a telecommunications network, which data signal is to be transmitted by at least one weighting vector from the transceiver 1 to a terminal 2. For improving such a method, the invention comprises: receiving signals transmitted by the transceiver 1 at the terminal 2; determining for each antenna element a value w(i) indicative of the short term variations; transmitting the values w(i) to the transceiver 1; estimating, based on those values w(i), coefficients e(i) indicative of the stationary structure of the received signals; and weighting the data signal S in the antenna elements with the coefficients e(i). Alternatively, such coefficients e(i) are determined already in the user equipment 2 and transmitted in bursts to the transceiver 1 for controlling the distribution of a data signal to the antenna elements. Similar methods are proposed for soft handover.

Abstract: The present invention discloses a method for determining user channel impulse response in the TD-SCDMA system, including: setting one or more than one synchronous ID code and establishing corresponding relations between channel estimation parameters of each user and the synchronous ID code and a sub-frame number of a sub-frame transmitting the synchronous ID code; transmitting, by each user, a corresponding synchronous ID code in a sub-frame identified by a sub-frame number corresponding to channel estimation parameters according to the relations established in step A, wherein timing advance of transmitting the synchronous ID code is the same with that of transmitting uplink service data of the user; at Node B, continuing to detect whether there is the synchronous ID code in received signals, if there is one or more than one synchronous ID code, determining the channel estimation parameters of the user transmitting the synchronous ID code according to the detected synchronous ID code, sub-frame number of the

Abstract: Method for transmitting a word representative of transmission parameters respectively allocated to the mobile stations in communication with a base station of a mobile telecommunication system, wherein it includes the step of: including, in each transmission burst a midamble resulting from the sum of selected midambles among all the available midambles, said selection being done by said base station in relation with a word so that the selected midamble corresponds to a binary element of said word equal to a first value and a non-selected midamble corresponds to a binary element of said word equal to a second value, and considering a word the elements of which are in one-to-one relationship with the temporal positions of the estimations respectively corresponding to said available midambles.