Abstract: A method of determining a set of Zero Correlation Zone (ZCZ) lengths, comprises: determining the length of a root sequence, and selecting such a set of ZCZ lengths that, for any cell radius, the maximum number of preambles obtained from a ZCZ length which is selected from the selected set of ZCZ lengths is closest to the maximum number of preambles determined from a ZCZ length which is selected from the set of all integers, wherein the maximum number of preambles is determined from the length of the root sequence and a ZCZ length selected. This disclosure provides a technical solution for selecting a better limited set of ZCZ lengths by which signaling overload is reduced.

Abstract: A method of allocating communication resources for a communication between a transmitter and a receiver in a communication system, the communication resources being divided in time periods and frequency sub-bands. The transmitter receives a channel quality measurement sent by the receiver. The transmitter performs allocation of a first part of the communication resources to the receiver according to the channel quality measurement if allocation of the first part is selected, or allocation of a second part of the communication resources to the receiver if allocation of the first part is not selected. The transmitter informs the receiver of allocated communication resources, and the allocated communication resources being designated for frequency localized channels or for frequency distributed channels.

Abstract: A method can be used for facilitating an uplink synchronization between a first transceiver and a second transceiver within a cell in a multi-user cellular communication system. The first transceiver receives a reference from the second transceiver and generates a set of signature sequences based on the reference. The first transceiver selects a first signature sequence from the set of signature sequences and incorporates the first signature sequence into a signal. The first transceiver transmits the signal to the second transceiver. The signal is used for a uplink synchronization between the first transceiver and the second transceiver. The set of signature sequences are generated from sequences with zero-correlation zone.

Abstract: The present invention relates to a method for allocating communication resources in a multi-user cellular communication system, wherein communication resources are divided in time periods and frequency sub-bands, wherein part of the communication resources are used for frequency-localized communication channels, and part of the communication resources are used for frequency distributed channels. The method further comprises the steps of classifying part of the frequency sub-bands as frequency sub-bands carrying frequency-distributed channels, classifying the remaining part of the frequency sub-bands as frequency sub-bands carrying frequency-localized channels. The present invention also relates to a system, a transmitter and a communication system.

Abstract: Method and apparatus are provided for transmitting a random access preamble in a mobile communication system. The preamble is selected from a set of random access preambles provided with Zero Correlation Zones of length NCS?1, where NCS is a cyclic shift increment selected from a set of cyclic shift increments {0, 13, 15, 18, 22, 26, 32, 38, 46, 59, 76, 93, 119, 167, 279, 419}, and transmitted.

Abstract: A method and apparatus for frequency offset estimation exploits the differences in reference symbol timing for different channels to resolve ambiguities in the frequency offset estimation. Based on the initial frequency offset estimates, a hypothesis table is constructed providing hypothesized frequency offsets for each channel for a plurality of possible offset regions. An error metric for each offset region is calculated based on the difference of the hypothesized frequency offsets. The set of hypothesized frequency offsets that minimize the error metric is selected as the final frequency offset estimates.

Abstract: A method can be used for facilitating uplink synchronization between a first transceiver and a second transceiver within a cell in a multi-user cellular communication system. The first transceiver receives a signal for the uplink synchronization from the second transceiver. The signal includes a first signature sequence generated, at least in part, from a sequence with a zero-correlation zone. The first transceiver then performs a correlation of the signal for detection of the first signature sequence.

Abstract: A method can be used for facilitating an uplink synchronization between a first transceiver and a second transceiver within a cell in a multi-user cellular communication system. The first transceiver receives a reference from the second transceiver and generates a set of signature sequences based on the reference. The first transceiver selects a first signature sequence from the set of signature sequences and incorporates the first signature sequence into a signal. The first transceiver transmits the signal to the second transceiver. The signal is used for a uplink synchronization between the first transceiver and the second transceiver. The set of signature sequences are generated from sequences with zero-correlation zone.

Abstract: A basic idea is to determine (S1) occurrence of a glitch caused by operation of the AGC mechanism, identify (S2) those modulation symbols in a digitized version of the received signal that are affected by the glitch, each modulation symbol represented by a number of bits in combination, and then reduce (S3), for each of the identified modulation symbols, the contribution in representing the identified modulation symbol as provided by at least a subset of the bits of the modulation symbol. In this way, the adverse effects of the glitch can be effectively mitigated and subsequent detection of the desired signal can be significantly improved. This also means that the link performance will be significantly improved.

Abstract: A method in a base station for detecting a HARQ-ACK codeword comprised in a signal received from a UE is provided. The base station knows HARQ-ACK codewords being possible to detect. The base station receives (401) a signal from the UE comprising a modulation symbol. The base station estimates (402) a SNR value for the received signal, and calculates (403) soft values for the modulation symbol. When the SNR value is lower than a predetermined threshold value and when the modulation symbol of the received signal comprises more than two bits per modulation symbol, the base station uses a first mode. The first mode comprises correlating (405) only the two first calculated soft values for the modulation symbol with the one or more known possible HARQ-ACK codewords. In other cases, i.e. when the first mode is not used, the base station uses a second mode. The second mode comprises correlating (408) all calculated soft values for the modulation symbol with the known possible HARQ-ACK codewords.

Abstract: A method for uplink synchronization of a first transceiver and a second transceiver in a multi-user cellular communication system having communication resources divided into communication channels. The method includes the following steps. A first signature sequence is transmitted from the second transceiver to the first transceiver, where the signature sequence is selected from a first set of signature sequences. In the first transceiver, the received signal is correlated with at least one signature sequence from a second set of signature sequences to estimate the time of arrival of the signature sequence to synchronize transmission between the second transceiver and the first transceiver. In transmitting the first signature sequence from the second transceiver to the first transceiver, the first signature sequence constitutes at least part of a zero-correlation zone sequence.

Abstract: Method and apparatus are provided for transmitting a random access preamble in a mobile communication system. The preamble is selected from a set of random access preambles provided with Zero Correlation Zones of length NCS?1, where NCS is a cyclic shift increment selected from a set of cyclic shift increments {0, 13, 15, 18, 22, 26, 32, 38, 46, 59, 76, 93, 119, 167, 279, 419}, and transmitted.

Abstract: Systems and methods provide for an increase in hearability by a user equipment (UE, 116). This increase in hearability can be used to improve positioning results. Two different types of positioning subframes can be transmitted by cells in a radio access network (RAN) to improve hearability: measurement subframes and low-interference subframes. The selection of which type of positioning subframe to transmit can be determined algorithmically by the transmitting entity.

Abstract: The present invention generates exponents of elements of a Zadoff-Chu sequence representing a preamble for uplink synchronization of mobile stations or a mobile station reference signal by first obtaining (S1) a preamble index defining the Zadoff-Chu sequence. Then it determines an initial exponent (S3) of the first element in the Zadoff-Chu sequence and an initial first difference (S2, S4) between exponents of consecutive elements of the Zadoff-Chu sequence. Finally it determines (S5-S9) exponents of the remaining elements in the Zad-off-Chu sequence from the initial first difference and the initial exponent in an iterative procedure that avoids multiplication operations.

Abstract: A detection method for ACK/NACK includes the steps of: (a) calculating a threshold between ACK and DTX, which includes two values, the first being proportional to a noise standard deviation after despreading the received signal, and the second depending on an estimated received signal for ACK, (b) calculating a threshold between NACK and DTX, which includes two values, the first being proportional to a noise standard deviation after despreading the received signal, and the second depending on an estimated received signal for NACK, (c) selecting the threshold with maximum absolute value from the two calculated values of the threshold between ACK and DTX, (d) selecting the one with maximum absolute value from the two calculated values of the threshold between NACK and DTX, and (e) comparing a decision variable with the two selected thresholds.

Abstract: A method of determining a set of Zero Correlation Zone (ZCZ) lengths, comprises: determining the length of a root sequence, and selecting such a set of ZCZ lengths that, for any cell radius, the maximum number of preambles obtained from a ZCZ length which is selected from the selected set of ZCZ lengths is closest to the maximum number of preambles determined from a ZCZ length which is selected from the set of all integers, wherein the maximum number of preambles is determined from the length of the root sequence and a ZCZ length selected. This disclosure provides a technical solution for selecting a better limited set of ZCZ lengths by which signaling overload is reduced.

Abstract: A method for correlation of an input signal in a receiver is disclosed as well as a receiver and a communication system for implementing the method. The input signal is correlated with Generalized Chirp-Like (GCL) sequences being derived from a single Zadoff-Chu sequence modulated with at least two modulation sequences. The method includes at least the steps of processing samples of the input signal in a first delay line, in a Discrete Fourier Transform (DFT) circuit and in a second delay line. According to the invention, a multiplication of samples of the input signal with elements of modulation sequences corresponding to the at least two modulation sequences being used for deriving the GCL sequences is performed in a step after the processing in the first delay line. Then a DFT processing is performed using a DFT circuit.

Abstract: A method for uplink synchronization of a first transceiver and a second transceiver in a multi-user cellular communication system having communication resources divided into communication channels. The method includes the following steps. A first signature sequence is transmitted from the second transceiver to the first transceiver, where the signature sequence is selected from a first set of signature sequences. In the first transceiver, the received signal is correlated with at least one signature sequence from a second set of signature sequences to estimate the time of arrival of the signature sequence to synchronize transmission between the second transceiver and the first transceiver. In transmitting the first signature sequence from the second transceiver to the first transceiver, the first signature sequence constitutes at least part of a zero-correlation zone sequence.

Abstract: A detection method for ACK/NACK includes the steps of: (a) calculating a threshold between ACK and DTX, which includes two values, the first being proportional to a noise standard deviation after despreading the received signal, and the second depending on an estimated received signal for ACK, (b) calculating a threshold between NACK and DTX, which includes two values, the first being proportional to a noise standard deviation after despreading the received signal, and the second depending on an estimated received signal for NACK, (c) selecting the threshold with maximum absolute value from the two calculated values of the threshold between ACK and DTX, (d) selecting the one with maximum absolute value from the two calculated values of the threshold between NACK and DTX, and (e) comparing a decision variable with the two selected thresholds.

Abstract: The present invention relates to a method for allocating communication resources in a multi-user cellular communication system, wherein communication resources are divided in time periods and frequency sub-bands, wherein part of the communication resources are used for frequency-localized communication channels, and part of the communication resources are used for frequency distributed channels. The method further comprises the steps of classifying part of the frequency sub-bands as frequency sub-bands carrying frequency-distributed channels, classifying the remaining part of the frequency sub-bands as frequency sub-bands carrying frequency-localized channels. The present invention also relates to a system, a transmitter and a communication system.