Abstract: A method of transmitting a scheduling request which is used to request a radio resource for uplink transmission includes configuring an uplink control channel for transmission of a scheduling request in a subframe, the subframe comprising two consecutive slots, a slot comprising a plurality of single carrier-frequency division multiple access (SC-FDMA) symbols, the scheduling request being carried by presence or absence of transmission of the uplink control channel, and transmitting the scheduling request on the uplink control channel.

Abstract: An orthogonal frequency division multiplexing (OFDM) transmitting apparatus including a signal processing unit, a subcarrier orthogonalization processing unit, and a transmitting unit is provided. The signal processing unit divides a received signal into several real parts and several corresponding imaginary parts. The subcarrier orthogonalization processing unit is coupled to the signal processing unit for receiving the real and the imaginary parts of the signal, and for making the real and the imaginary parts respectively carried by a plurality of different and orthogonal subcarriers. The transmitting unit is coupled to the subcarrier orthogonalization processing unit to transmit the subcarriers.

Abstract: For a data group composed of pieces of data each indicating channel characteristics of a scattered pilot signal position whose phase is adjusted by dividing scattered pilot signals included in an OFDM signal by a scattered pilot signal at the time of transmission, a carrier extension circuit 341 inserts data having a same value as a value of data of a lower end into an outside of the lower end of a band, and inserts data having a same value as a value of data of an upper end into an outside of the upper end of the band. On the data group composed of 2N pieces of data including the data inserted by the carrier extension circuit 341, IFFT processing by an IFFT circuit 342, noise removal processing by a noise removal filter 343, and FFT processing by a FFT circuit 344 are performed. The data inserted by the carrier extension circuit 341 is removed from the data group outputted from the FFT circuit 344, and the data group after the data removal is used for interpolation in a symbol direction.

Abstract: A transmission of information within a wireless cellular network may include a first and second group of samples. A first group of samples is created comprising at least a first and a last subgroup, wherein the last subgroup is same as the first subgroup. A second group of samples created. A transformed set of samples produced by jointly transforming the created first and second group with a discrete Fourier transform (DFT). The transformed set of samples is expanded to produce an expanded set, and the expanded set is transformed with an inverse discrete Fourier transform (IDFT) to produce an OFDM symbol with a fractional payload. The first group of samples is a reference signal (RS), which is known to the receiver before the transmission occurs, while the second group of samples is information data.

Abstract: A method of generating a reference signal includes acquiring a base sequence and acquiring a reference signal sequence with a length N from the base sequence. Good PAPR/CM characteristics of the reference signal can be kept to enhance performance of data demodulation or uplink scheduling.

Abstract: A system samples data of a digital pulse. The system includes a processor, an integrator, and a converter. The processor computes a discrete Fourier transform of frequency data of the digital pulse. The discrete Fourier transform includes a first output. The integrator integrates the first output to produce phase data. The phase data includes a second output. The converter applies an inverse discrete Fourier transform to the second output to produce a continuous signal that may be sampled at a predetermined time instant.

Abstract: An apparatus for generating sets of radio parameters includes a first deriving unit deriving a set of radio parameters for specifying a symbol including an effective symbol part with the same period as the effective symbol part specified by another set of radio parameters and a guard interval part with a different period from the guard interval part specified by the other set of radio parameters. The apparatus further includes a second deriving unit deriving a set of radio parameters so that an occupancy proportion of the guard interval part in a single symbol specified by another set of radio parameters is equal to an occupancy proportion of the guard interval part in a single symbol specified by the other set of radio parameters.

Abstract: Methods and arrangements for wireless communications are described. Embodiments include transformations, code, state machines or other logic to receive from a transmitter a signal representing a known sequence of symbols. The signal may be transmitted over a plurality of sub channels. The embodiments may also include determining channel responses at the sub channels and determining a reception of the known sequence. The determining may include treating the channel responses at the sub channels in a differential manner to cancel out channel phase responses and obtain channel amplitudes. In some embodiments, the cancelling may be performed by multiplying frequency domain values representing reception of a sub channel by the complex conjugate of frequency domain values of a neighboring sub channel. Many embodiments may also include calculating a carrier to interference and noise ratio (CINR) of the signal. In several embodiments, the signal may represent the preamble of a wireless frame.

Abstract: An apparatus, such as a user equipment, includes a resource unit RU measurement unit coupled to an output of a wireless receiver; an encoder configurable to encode information descriptive of M perceived best ones of N RUs, where each individual RU is assigned a unique number from a set {1,2, . . . ,N}, where there are sets: SM={n=(nm)m=1M:1?n1<n2<. . . <nM?N}, ={l, 2, ?,|SM|}, where each vector in set SM refers to a unique RU combination and where there are ? S M ? = ( N M ) elements in the set SM; and a wireless transmitter configurable to transmit the encoded information to a wireless network apparatus, such as a base station. The base station includes a decoder operable to decode the encoded information.

Abstract: In an OFDM transmission method, in order to compensate any frequency response variation time wise resulted from any distortion in a transmission path, out-of-synchronization with passage of time, frequency drift, and phase shift, and to improve a demodulation characteristic, a PS detector in a receiver receiving an OFDM signal detects a pilot symbol. A PS1 TPFR calculator calculates a frequency response of the transmission path for a first pilot symbol, while a PS2 TPFR calculator calculates a frequency response of the transmission path for a second pilot symbol. Thereafter, a compensation vector calculator calculates compensation vectors from the frequency responses of the transmission path for both the first and second pilot symbols by linear approximation. A frequency response compensator compensates the frequency response variation of subcarriers in a data symbol based on the calculated compensation vectors.

Abstract: Described is a method for compensation of an OFDM signal propagating through Doppler-distorted, time-varying multipath channels. The method is based on low-complexity post-FFT signal processing. Minimum mean square error combining of signals is performed for signals received at spatially-distributed receiver elements using adaptive channel estimation and phase tracking. Doppler shifts are modeled as a consequence of motion-induced time compression and dilation. The Doppler rate is assumed constant over one OFDM block but can vary between OFDM blocks. Thus a non-constant Doppler shift is accommodated by the method. Non-uniform Doppler compensation across subchannels is based on adaptive estimation and prediction of the Doppler rate. A single adaptively estimated parameter is used to track the phases of all the carriers and channel estimates are updated on a block by block basis.

Abstract: A method for frequency offset estimation in frequency domain is provided. The method comprises the following steps. First, a phase angle of a signal field of the input signal after processed by Fast Fourier Transformation (FFT) and channel equalization is calculated. A frequency offset error originated from at least one frequency offset estimation process in time domain is then estimated according to the phase angle.

Abstract: A receiver of an OFDM signal includes a reception unit to receive an OFDM signal formed by a plurality of OFDM symbols respectively including data subcarriers to which data signals are allocated and pilot subcarriers to which cyclically shifted pilot signals are allocated in frequency domain, an estimator to estimate phase errors of the pilot signals to generate first estimated values related to an offset of the OFDM symbol corresponding to each two or more OFDM symbols in the OFDM signal, a weighting adder to perform weighting additions on the first estimated values to obtain one second estimated value related to the offset, a compensator to compensate the offset by using the second estimated value to obtain a compensated OFDM signal, and a decoder to decode the compensated OFDM signal to reproduce the data signals.

Abstract: This document is related to a method for receiving signals in multi-user system, the method comprising: receiving signals form 2 or more mobile stations using ‘k’-th radio resource and ‘k+m’-th radio resource; estimating a channel matrix using the received signals; calculating a weight matrix so that the channel matrix have an orthogonality to the signals from each of the mobile stations; transmitting the weight matrix to each of the mobile stations; and receiving signals that the weight matrix is applied by each of the mobile stations. By doing so, we can increase the transmission efficiency through obtaining both orthogonality and diversity gain in the multi-user MIMO system.

Abstract: A multicarrier communication system is provided that divides a full frequency band into a plurality of sub-carrier frequency bands, generates a plurality of segments having a frequency-time domain occupied by a predetermined number of sub-frequency bands and a predetermined number of time intervals, and classifies a plurality of segment types according to each of the segments, for data transmission. A mobile subscriber (MS) measures a channel state, extracts channel state information corresponding to the channel state, estimates a segment type using the extracted channel state information, and if there is a need for a change in the segment type, the MS transmits a segment type change request message to a base station (BS). Upon receiving a segment type change grant message from the BS, the MS receives data in a segment type corresponding to the received message.

Abstract: An apparatus for automated acquisition of a QAM signal. The apparatus employs a State machine progressing from an initial State to a final State. The State Machine comprises: (A) an AGC State further comprising a Minimum Sub-State further comprising: Coarse Estimate Sub-State; and an AGC Lock Sub-State further comprising Maximum Sub-State; (B) a Clock 1 State further comprising a Minimum Sub-State, and a Maximum Sub-State; (C) a Clock 2 State further comprising: a Minimum Sub-State; and a Maximum Sub-State; and (D) a Blind State further comprising a Minimum Sub-State; a Threshold Sub-State further comprising a Maximum Sub-State; and a Hysteresis Sub-State.

Abstract: The invention relates to a method for reducing the crest factor, comprising the following method steps: (a) IFFT transformation of a data symbol to be transmitted; (b) looking for all peak values within a frame of the IFFT-transformed data symbol the amount of which is above a predetermined threshold; (c) providing a sample correction function; (d) allocating a scaling and phase rotation to the sample correction function according to the amplitude and position of the peak values found; (e) generating a correction signal in the frequency domain from a linear combination of rotated and scaled vectors according to the scaling and position determined; (f) modifying, particularly reducing the peak value of the data symbol to be transmitted by subtracting the correction signal, and IFFT transformation of the peak-value-modified data symbol into the time domain. The invention also relates to a circuit for reducing the crest factor.

Abstract: Position location signaling system, apparatus, and method are disclosed. Position location beacons can each be configured to transmit a frequency interlaced subset of orthogonal frequencies spanning substantially an entire channel bandwidth. The orthogonal frequencies can be pseudorandomly or uniformly spaced, and each beacon can be allocated an equal number of orthogonal frequencies. Each frequency of the interlaced subset of orthogonal frequencies can be modulated with an element of a predetermined data sequence. A mobile device can receive one or more of the beacon signals and determine a position using a position location algorithm that determines position in part on an arrival time of the beacon signal. Where the mobile device can receive three or more beacon signals, the mobile device can perform position location by trilateration to the beacon positions based, for example, on a time difference of arrival.

Abstract: An Orthogonal Frequency Division Multiplexing (OFDM) receiver comprises: a channel estimator receiving a signal that includes a plurality of symbols, each of the symbols including a plurality of pilots and a plurality of data subcarriers, wherein each symbol further includes at least one pilot subcarrier, the estimator using a first channel response estimate of the at least one pilot subcarrier in a first symbol to select a first weight matrix from a plurality of pre-generated weight matrices, and generating channel estimation information for data subcarriers in the first symbol using the selected first weight matrix.

Abstract: Methods and systems for subpacket generation using a convolutional turbo code in hybrid automatic repeat request re-transmissions that includes separating a codeword into subblocks of bits, interleaving the subblocks, and performing a permutation to group the bit streams and rearrange a symbol constellation such that bits are assigned to bit positions based on a number of re-transmissions.

Abstract: In an OFDM receiver, one of a plurality of antennas is selected based on a ratio X of two moving average integration values (first moving average integration value and second moving average integration value) that are calculated from a non-delay symbol and a delay symbol. It could be said that the second moving average integration value represents excessive false information (that is, whether the state of the transmission line is good). Accordingly, determination of the ratio X between the second moving average integration value and the first moving average integration value and selection of one of the plurality of antennas based on the ratio X enables judgment on whether the state of the transmission line is good even during a period other than a guard interval period Tg, that is, during an effective symbol period Tu.

Abstract: Implementations related to media playback and storage devices are presented herein.

Abstract: A device and method for performing channel estimation for an OFDM-based wireless communication system modifies pilot subcarrier spacing to use a set of interpolation coefficients associated with a different pilot subcarrier spacing.

Abstract: A fixed-point IFFT device in an OFDMA digital modulator is disclosed, which comprises a sub-carrier activity detector configured to detect a number of active sub-carriers in an OFDMA symbol set being transmitted in a given OFDMA symbol period, a scale termination calculator configured to generate an output for determining at which stage to terminate the IFFT scaling as a predetermined function of the number of active sub-carriers, a scaling controller configured to generate a plurality of control signals based on the output of the scale termination calculator, and an IFFT unit having a plurality of scaling stages each of which is controlled by one of the generated control signals.

Abstract: A network node self-retirement apparatus, system, and method is provided. The system includes a first network node, a second network node, and a plurality of network nodes. The first network node is configured to monitor a power and traffic level of the first network node and determine an operational weight based thereon. The first network node is further configured to compare the operational weight to a selected operational weight to determine a relationship between the operational weight and the selected operational weight. The first network node is further configured to execute a network node self-retirement procedure when the relationship satisfies a selected condition and to send the operational weight to at least one network node when the relationship does not satisfy the selected condition. The first network node may also determine a network topology based on operational weights received from other network nodes.

Abstract: A system (100) and method (400) for peak limiting suitable for use in a communication system is provided. The method can include modulating (402) a symbol vector to produce a modulated waveform (500), wherein the symbol vector contains at least one symbol in at least one subcarrier (130), computing (404) at least one symbol adjustment that is based on at least one peak overshoot (512) of the modulated waveform, and applying (406) the at least one symbol adjustment to the symbol vector in accordance with an assigned weighting for reducing a peak power of the modulated waveform. The method limits an energy in the at least one subcarrier to a prespecified level of distortion.

Abstract: Control channel information is formulated for transmission in orthogonal frequency division multiplexing (OFDM) systems. In an example embodiment, a method entails formulating control channel information for a transmitting device operating in an OFDM system in which a control channel spans n OFDM symbols, with n being an integer. The method includes acts of allocating, creating, and mapping. Control channel data is allocated to at least one set of resource element groups. At least one order for the set of resource element groups is created in accordance with one or more permutation mechanisms that involve at least one interleaving sequence having a low cross-correlation property. The set of resource element groups is mapped to resource elements of the n OFDM symbols of the control channel responsive to the order that is created using the permutation mechanism(s). The permutation mechanisms may include interleaving sequence(s) and/or cyclic shift(s).

Abstract: In some embodiments of the present invention there is provided a frame structure for transmitting an integer number of OFDM symbols in which some of the OFDM symbols are to be transmitted in a unicast format and some of the OFDM symbols are to be transmitted in a broadcast format. The frame structure includes partitioning of a frame into at least two portions to accommodate both unicast and broadcast modes in the frame. The frame structure is used for transmitting multiple frames in a serial manner from at least one transmitter. The unicast mode supports transmission of OFDM symbols from a single transmitter to a single receiver. The broadcast mode supports transmission of OFDM symbols from multiple transmitters to all receivers within range of the multiple transmitters. The multicast mode supports transmission of OFDM symbols from multiple transmitters to multiple receivers within range of the multiple transmitters.

Abstract: A method of configuring a sub-slot having a layer-modulated multi-user packet (MUP) is disclosed. More specifically, the method comprises modulating symbols associated with a first layer by using non-layered modulation scheme, and modulating symbols associated with a second layer and a third layer using a different layered-modulation scheme. Here, the symbols associated with the second layer and the third layer are multiplexed by any one of an orthogonal frequency division multiplexing, a code division multiplexing, a multi-carrier code division multiplexing, or a time division multiplexing.

Abstract: A gap filler apparatus providing cyclic delay diversity in a digital multimedia broadcasting (DMB) system. In the gap filler apparatus, a receiver receives an orthogonal frequency division multiplexing (OFDM) signal transmitted as a broadcasting signal. A symbol synchronization unit acquires symbol synchronization of the OFDM signal, detects a guard interval of an OFDM symbol using the symbol synchronization, determines a sample length, by which the OFDM symbol is cyclic-delayed within the guard interval, and cyclic-delays the OFDM signal by the determined sample length. An amplifier amplifies the cyclic-delayed OFDM signal. A transmitter transmits the amplified OFDM signal to a wireless network.

Abstract: A method allocates bandwidth to channels in an orthogonal frequency division multiple access and time division multiple access (TDMA) network. The network includes a master device (master) communicating with a set of slave devices (slaves). The master defines a set ?m of logical indices ? of a set of N physical subcarriers for a set of M data streams to be allocated to a set of Nd logical data subcarriers according to ?m={?|?=iM+m, i=0,1,2, . . . , d?1}, where d=Nd/M. The set of N data subcarriers is mapped to the set of Nd logical subcarriers according to the logical indices, and the data subcarriers are allocated to the logical subcarriers.

Abstract: A method for successive interference cancellation in code division multiple access (CDMA) systems is provided that uses variable interferer weights. This method allows interfering signals to be cancelled in order to recover a transmitted data signal. This method involves receiving the data signal subject to interference from at least one interfering signal. A first interfering signal is identified. Then an interferer weight coefficient associated with the first interfering signal is generated. This allows the first interfering signal to be cancelled from the received data signal using the interferer weight coefficient. These processes may then be reiterated for other interfering signals. It is then possible to recover the transmitted data signal from the received data signal.

Abstract: Methods and structures are disclosed for use in implementing downlink spatial division multiple access (SDMA) in a wireless network. In at least one embodiment, a number of orthogonal sets of user devices are first identified within a coverage area. One of the identified orthogonal sets may then be selected based on a predetermined selection criterion. An SDMA exchange may then be initiated for the selected orthogonal set.

Abstract: A rate matching method and device wherein the number of times to output each bit included in input data is determined in parallel, and the data length of the input data is expanded or contracted, based on basic parameters for expanding or contracting the input data and the bit number (m) of each bit of the input data. A de-rate matching method and device is also disclosed wherein expanded or contracted data is decoded to pre-expanded/contracted data.

Abstract: An OFDM receiver having an analog multiplier based I-Q channelizing filter, samples and holds consecutive analog I-Q samples of an I-Q baseband, the I-Q basebands having OFDM sub-channels. A lattice of analog I-Q multipliers and analog I-Q summers concurrently receives the held analog I-Q samples, performs analog I-Q multiplications and analog I-Q additions to concurrently generate a plurality of analog I-Q output signals, representing an N-point discrete Fourier transform of the held analog samples, the I-Q signals having relative phase and magnitude representing bits in the OFDM sub-channels. The phase and magnitude may represent QPSK. Optionally, a phase shift decoder receives the analog transform I-Q output signals and generates a corresponding binary bit data.

Abstract: Techniques are disclosed involving preamble sequences. For instance, an apparatus includes a module to provide a preamble sequence having multiple values, where each of the values corresponds to an orthogonal frequency division multiplexing (OFDM) subcarrier. These multiple values may include multiple blocks of values based on a differentially encoded and scrambled row of a Hadamard matrix. The apparatus may further include a modulation module to produce an OFDM modulated signal from the preamble sequence. Further, techniques for the detection of such preambles are disclosed.

Abstract: An apparatus and method for determining a pilot pattern in a Broadband Wireless Access (BWA) communication system are provided. In the pilot pattern determining method, an Orthogonal Frequency Division Multiplexing (OFDM) demodulator generates frequency-domain data by fast-Fourier-transform (FFT)-processing a received signal. A pilot pattern decider calculates a coherence bandwidth and a coherence time using subcarrier values received from the OFDM demodulator, and selects one of a plurality of pilot patterns according to the ratio of the coherence bandwidth to the coherence time.

Abstract: Accordingly, a method and apparatus are provided to convert received content into a first stream and a second stream, to transmit said first stream using a first tone and to transmit said second stream using an orthogonal scheme. A layering scheme is used to transmit the base stream covering a smaller area and an enhanced stream is used to cover a large utilizing orthogonal scheme.

Abstract: A system and method for expanding traffic channels in a wireless communications system, such as CDMA2000, includes a method for generating a forward link signal including encoding each of a first set of channels with a mutually corresponding channel code, such as a Walsh code, selected from a predetermined set of channel codes, and encoding each of a second set of channels with the same mutually corresponding channel codes. A scramble code is applied to the encoded second set of traffic channels, which is combined with the encoded first set of traffic channels to form an extended forward link signal. Each channel code corresponds to two forward link channels, which are selectively decoded using the scramble code.

Abstract: Methods and apparatus for multi-carrier communication with variable channel bandwidth are disclosed, where the time frame structure and the OFDM symbol structure are invariant and the frequency-domain signal structure is flexible. In one embodiment, a mobile station, upon entering a geographic area, uses a core-band to initiate communication and obtain essential information and subsequently switches to full operating bandwidth of the area for the remainder of the communication. If the mobile station operates in a wide range of bandwidths, the mobile station divides the full range into sub-ranges and adjusts its sampling frequency and its FFT size in each sub-range.

Abstract: A digital modulation system provides enhanced multipath performance by using modified orthogonal codes with reduced autocorrelation sidelobes while maintaining the cross-correlation properties of the modified codes. For example, the modified orthogonal codes can reduce the autocorrelation level so as not to exceed one-half the length of the modified orthogonal code. In certain embodiments, an M-ary orthogonal keying (MOK) system is used which modifies orthogonal Walsh codes using a complementary code to improve the auto-correlation properties of the Walsh codes, thereby enhancing the multipath performance of the MOK system while maintaining the orthogonality and low cross-correlation characteristics of the Walsh codes.

Abstract: A wireless communication system, to control a peak power to an average power ratio because an amplifier characteristic of the wireless communication system include non-linear characteristic if input signal large the amplifier makes distortions. A wireless communication system comprises for suppressing a peak power to an average power ratio to process known signal like a pilot signal.

Abstract: Provided is a wireless communication apparatus by which the maximum throughput can be obtained while satisfying required reception qualities in multicarrier communication. In the apparatus, a coding section (101) performs error correction coding to all of the plurality of resource blocks at a same coding rate, modulating sections (103-1 to 103-n) generate data symbols by modulating coding data for each of the resource blocks (1 to n), and repetition sections (104-1 to 104-n) repeat the data symbols inputted from the modulation section (103) for each of the resource blocks (1 to n) to generate a plurality of same data symbols. Namely, while the coding rate is same in all of the resource blocks, modulation system and the number of repetitions differ by resource block.

Abstract: A relay apparatus for relaying a packet in radio communication by a wireless terminal in a communication area includes a packet monitoring part for obtaining data on a bandwidth to be used in the radio communication by the wireless terminal from a packet to be relayed, a bandwidth managing part for calculating and recording a total bandwidth in use used for the radio communication by the wireless terminal from the obtained data on a bandwidth, a retransmission adjusting part for determining an upper limit of a packet retransmission number, in accordance with an amount of an available bandwidth obtained by excluding a total bandwidth in use from a maximum bandwidth, and a retransmitting part for retransmitting a packet in a range not exceeding the upper limit of the packet retransmission number. Consequently, the relay apparatus enables retransmission appropriately adaptable to a use situation of a bandwidth by wireless communication of a wireless terminal in a communication area.

Abstract: A system for providing a fast access channel is disclosed. The system includes a transmitter configured to transmit a first long contention symbol and one or more subsequent long contention symbols. The first long contention symbol is followed by the subsequent long contention symbols. The system further includes a receiver configured to receive the first and subsequent long contention symbols and determine a contention code and a contention channel transmitted with the contention code based on the first and subsequent long contention symbols. Each of the first and subsequent long contention symbols includes a long cyclic prefix and a number of identical contention symbols.

Abstract: There is provided a receiver for processing a ranging channel. The receiver includes a Fourier transformer for transforming a received signal into a frequency domain signal, a ranging channel extraction and ranging code elimination unit for extracting a ranging channel from the frequency domain signal, and eliminating a code of a ranging code from the ranging channel and a ranging channel processor for estimating transmission delay or transmission power from a time domain signal. By estimating transmission delay and/or transmission power in a time domain, it is possible to rapidly and accurately adjust the transmission delay and transmission power intensity in the ranging procedure.

Abstract: A digital modulation system provides enhanced multipath performance by using modified orthogonal codes with reduced autocorrelation sidelobes while maintaining the cross-correlation properties of the modified codes. For example, the modified orthogonal codes can reduce the autocorrelation level so as not to exceed one-half the length of the modified orthogonal code. In certain embodiments, an M-ary orthogonal keying (MOK) system is used which modifies orthogonal Walsh codes using a complementary code to improve the auto-correlation properties of the Walsh codes, thereby enhancing the multipath performance of the MOK system while maintaining the orthogonality and low cross-correlation characteristics of the Walsh codes.

Abstract: A system and method for wireless communications using spatial multiplexing with incomplete channel information is provided. A method for wireless communications includes receiving a reference signal from a communications device, computing at least one first beamforming vector from the received reference signal, selecting at least one second beamforming vector from channel statistics, and transmitting information to the communications device. The reference signal is transmitted using a subset of antennas used for data reception at the communications device, and the transmitting uses the at least one first beamforming vector and the at least one second beamforming vector.

Abstract: The present invention proposes a method for generating synchronization bursts for OFDM transmission systems. The symbols of a predefined symbol sequence are mapped according to a predefined mapping scheme on subcarriers of the OFDM systems by a mapping unit (2), wherein the symbols of the predefined symbol sequence represent sub-carriers of the OFDM system with nonzero amplitudes. A synchronization burst is generated by a inverse fast Fourier transforming unit (3) transforming the subcarriers of the OFDM system mapped to said predefined symbol sequence. The mapping (2) of the symbols of the predefined symbol sequence is set such that the resulting time domain signal of the synchronization burst represents a periodic nature. According to the invention the predefined symbol sequence is set such that the envelope fluctuation of the time domain signal of the synchronization burst is minimized. Therefore advantageous symbol sequences reducing said the envelope fluctuation of the time domain signal are proposed.

Abstract: The present invention proposes a method for generating synchronization bursts for OFDM transmission systems. The symbols of a predefined symbol sequence are mapped according to a predefined mapping scheme on subcarriers of the OFDM systems by a mapping unit (2), wherein the symbols of the predefined symbol sequence represent subcarriers of the OFDM system with nonzero amplitudes. A synchronization burst is generated by a inverse fast Fourier transforming unit (3) transforming the subcarriers of the OFDM system mapped to said predefined symbol sequence. The mapping (2) of the symbols of the predefined symbol sequence is set such that the resulting time domain signal of the synchronization burst represents a periodic nature. According to the invention the predefined symbol sequence is set such that the envelope fluctuation of the time domain signal of the synchronization burst is minimized. Therefore advantageous symbol sequences reducing said the envelope fluctuation of the time domain signal are proposed.