Patent application number | Description | Published |
20080198800 | Method and Apparatus for Enhanced Uplink Data Transmission - The present invention provides a method and apparatus used for enhanced uplink data transmission, comprising the steps of: monitoring the communication status of a plurality of UEs (user equipment) which conduct uplink data transmission in the RAN; receiving the data transmitted on at least one dedicated uplink channel from at least one of the plurality of UEs; according to the communication status of the plurality of UEs, dynamically allocating the number of dedicated uplink channels for at least one UE of the plurality of UEs. Utilization of the present invention can enable mobile terminal to conduct more efficient uplink transmission. | 08-21-2008 |
20090067424 | METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING A DATA BLOCK IN A WIRELESS COMMUNICATION SYSTEM - The invention provides methods and apparatus for transmitting and receiving a source data block in a wireless communication system using hybrid automatic retransmission request protocol. According to the scheme provided by the invention, at transmitting side, the source data block or part of source data block that is not decoded correctly at receiving side is divided into a plurality of data segments, each the plurality of data segments may be paded with known data to expand the data segments to be a predetermined lengthen, the data segment is encoded with linear code to be a data packet including the data segment and a redundancy information segment or including only redundancy information, and after that the encoded data packets are transmitted. At the receiving side, when each of the received data packets includes a data segment and a redundancy information segment, decoding is performed directly based on the received data packet, decoding is performed based on the received redundancy information segment and an data segment and redundancy information segment extracted from buffered data packets with a first and second chance to restore the data segment that is not decoded correctly in previous decoding processing. With the additional decoding chance, the scheme provided by the invention can improve decoding probability and thus the transmission efficiency of the system. | 03-12-2009 |
20090252245 | TRANSMISSION METHOD AND APPARATUS FOR CANCELLING INTER-CARRIER INTERFERENCE - The present invention provides a transmission method and apparatus for cancelling inter-carrier interference in wireless communication systems. Particular carriers are not used for data transmission but carry weighted data to cancel the ici interference of a first group of interfering sub-carriers onto a second group of victim sub-carriers. The weights are inversely proportional to the frequency offset between the interfering sub-carriers and the victim sub-carriers. | 10-08-2009 |
20090310687 | METHOD AND APPARATUS FOR SPACE-TIME-FREQUENCY ENCODING AND DECODING - The present invention provides a space-time-frequency encoding and decoding method and apparatus used in a wireless communication system. With the encoding method provided in the invention, transmission code words and their redundant elements are properly allocated on space-time-frequency units, so that the transmission codes and their partial redundancies can be transmitted via different antennas. Accordingly, at the receiving side, the redundant elements and the corresponding code word elements can be combined, so as to enhance the SNR and diversity gains for a part of the elements in the code words, and hence enhance the reception quality for the overall data stream. | 12-17-2009 |
20100146354 | METHOD AND APPARATUS FOR H-ARQ IN A WIRELESS COMMUNICATION SYSTEM - The present invention discloses an H-ARQ scheme: In the case of wireless channel is in good condition, user equipment will send NACK signals and other control information only when it has received an incorrect data packet, otherwise the user equipment will not send ACK signals; in the case of wireless channel is in bad condition, existing H-ARQ schemes will be adopted. | 06-10-2010 |
20100177741 | METHOD FOR RESOURCE UNIT ALLOCATION FOR WIRELESS COMMUNICIATION, SUBSCRIBER STATION AND BASE STATION - A method for wireless communication between a base station and a plurality of subscriber stations is described wherein a communication capacity is partitioned in resource units at least by code multiplexing, which resource units are distributed by the base station over said devices, wherein data from each subscriber station is spread by means of a signature sequence, characterized in that multiple resource units assigned to a common subscriber station have the same signature sequence. | 07-15-2010 |
20100232532 | METHOD AND APPARATUS OF SPACE-TIME-FREQUENCY CODING - The invention relates to a space-time-frequency encoding for use in wireless communication systems. According to the encoding scheme provided by the invention, it first transforms a plurality of input element pairs into a plurality orthogonal element pairs respectively, each of the plurality of input element pairs and corresponding orthogonal element pair forming an orthogonal matrix; and then maps the first element, second element and the redundancy of the second element in each of the plurality of input element pairs and corresponding orthogonal element pair as channel elements to three predetermined time-frequency cells in a first and second two-dimension time-frequency matrix so as to make the channel elements in the first and second matrixes suitable for being transmitted via different antennas. As the redundant input element pairs and corresponding orthogonal element pairs transmitted via different antenna are orthogonal in both space-time domain and space-frequency domain at the same time, and thus two-dimension space-time transmit diversity gain and space-frequency transmit diversity gain can be achieved at the same time. | 09-16-2010 |
20100254473 | METHOD AND SYSTEM FOR MANAGING PRECODING IN A MULTI-USER WIRELESS COMMUNICATIONS SYSTEM - Operating a wireless communications system that supports multi-user multiple-input multiple-output (MU-MIMO) communications between a base station and multiple mobile stations involves generating a channel estimation, predicting a future channel estimation from the channel estimation, precoding data in response to the predicted future channel estimation, and transmitting the precoded data. | 10-07-2010 |
20100284353 | METHOD AND SYSTEM FOR MANAGING TRANSMISSION RESOURCES IN A WIRELESS COMMUNICATIONS SYSTEM - A technique for managing the transmission resources in a wireless communications system ( | 11-11-2010 |
20100311428 | RANDOM ACCESS PREAMBLE CELLULAR PHONE SYSTEMS WITH MULTIPLE ZADOFF-CHU SEQUENCES - A cellular phone system where a random access channel burst has a preamble comprising two Zadoff-Chu sequences to mitigate the effects of Doppler Frequency Offset. Upon reception of a random access channel burst by a base station, division is applied to the two sequences recovered from the preamble of the received burst to provide a quotient sequence. For some embodiments, the base station correlates the quotient sequence with a Zadoff- Chu sequence to identify the user equipment that transmitted the random access channel burst. Other embodiments are described and claimed. | 12-09-2010 |
20110142151 | AN ADAPTIVE SCHEME TO DETERMINE THE SUB-CARRIER SPACING FOR MULTI-CARRIER SYSTEMS - Orthogonal Frequency Division Multiplexing (OFDM) is a typical multi-carrier technique that has been applied by many advanced wireless communication systems, e.g., 3GPP Long Term Evolution (LTE) and WiMAX. In order to support high mobility transmission, the sub-carrier spacing of multi-carrier systems is made large enough to overcome the Doppler frequency offset. However, this large sub-carrier spacing results in lower transmission efficiency since the CP (Cyclic Prefix) consumes a considerable of radio resources. The present invention provides an adaptive scheme to determine the sub-carrier spacing in which the default sub-carrier spacing is set to support lower mobility, while the adaptively adjusted sub-carrier spacing based on User Equipment (UE) mobile velocities is set to support higher mobility. | 06-16-2011 |
20120002576 | METHOD AND SYSTEM FOR AVOIDING INTERFERENCE CAUSED BY NON-SYNCHRONIZATION IN RELAY TDD SYSTEM - The present invention provides a method and a device for eliminating interference in a wireless relay TDD system. Data is sent between a relay station and a base station by occupying time slots of guard period, thereby the interference caused by non-synchronization between the base station and the relay station is eliminated. | 01-05-2012 |
20120014312 | METHOD AND DEVICE FOR CONTROLLING PROPAGATION DELAY IN A COMP TRANSMISSION SYSTEM - The present invention proposed a method and a device for controlling propagation delay in a base station of a wireless communication system based on COMP transmission. To be specific, w hen sending downlink data to a mobile station, the base station processes part of data of one or more other unsynchronized base stations and sends the processed part of data to the mobile station at one or more specific time slots simultaneously. By applying the solution of the present invention, because data, corresponding to the length of the out-of-synchronization information, of an unsynchronized base station is sent to the mobile station at a specific time slot by a synchronized base station or other unsynchronized base stations, DL data that is sent to the mobile station by the unsynchronized base station all falls within the detection window of the mobile station, such that the resulted problem of the decreased performance of a receiver due to the propagation delay is solved. | 01-19-2012 |
20120026936 | METHOD, APPARATUS AND DEVICE FOR RELAY USER SELECTION AND DOWNLINK RESOURCE ALLOCATION - The present invention proposes a method, apparatus and device for relay user selection and downlink resource allocation in a base station of a relay communication system. Specifically the base station performs relay user selection and downlink resource allocation according to a pattern of a cell-specific reference signal thereof and/or a reception demodulation scheme of a mobile terminal. With the method, apparatus or device according to the invention, it is possible to alleviate and even eliminate influence of overlapping cell-specific reference signals upon the performance of reception demodulation at a user terminal. | 02-02-2012 |
20120140851 | METHOD OF MAINTAINING COHERENCY OF A PRECODING CHANNEL IN A COMMUNICATION NETWORK AND ASSOCIATED APPARATUS - In prior art, selection of precoding granularity is affected by two inter-restricting factors, i.e., precoding accuracy and channel estimation at a mobile terminal. To solve this problem, the present invention provides a method of maintaining coherency of a precoding channel in a communication network and an associated apparatus. During precoding, this method takes into account both channel coherency and system capacity. A base station adjusts phase and/or amplitude of a precoding matrix corresponding to each precoded unit to maintain coherency of associated information of the overall precoding channel. The associated information of the precoding channel includes, for example, CSI or eigenvalue matrix of the precoding channel. Afterwards, a mobile terminal performs channel estimation based on reference signals of multiple precoded units, thereby eliminating the limitation in prior art that a mobile terminal can perform channel estimation only within one or more resource block limited by a precoding granularity. | 06-07-2012 |
20130279620 | METHODS OF TRANSMITTING COORDINATE MULTIPLE POINT DATA BASED ON ORTOGONAL COVERING CODES - The present invention relates to methods of transmitting coordinate multiple point data based on orthogonal covering codes. In an embodiment of the present invention, there is provided a method of transmitting downlink data in a base station of a multiple input multiple output system. The method includes: A. determining a plurality of antenna groups from antennas of a plurality of coordinate multiple point cells; B. modulating inter-cell coordinate multiple point downlink data symbols for each antenna groups using different orthogonal covering codes. The orthogonal covering codes have a length not greater than twice the number of the antenna groups. With the methods of the present invention, a base station and a user equipment can distinguish signals from different coordinate multiple point cells, different antenna groups, or different coordinate multiple point clusters, reducing interference between signals from the different coordinate multiple point cells, the different antenna groups, or the different coordinate multiple point clusters. | 10-24-2013 |
20130308587 | TRANSMISSION METHOD AND APPARATUS FOR CANCELLING INTER-CARRIER INTERFERENCE - The present invention provides a transmission method and apparatus for cancelling inter-carrier interference in wireless communication systems. Particular carriers are not used for data transmission but carry weighted data to cancel the ici interference of a first group of interfering sub-carriers onto a second group of victim sub-carriers. The weights are inversely proportional to the frequency offset between the interfering sub-carriers and the victim sub-carriers. | 11-21-2013 |
20130322288 | METHOD OF DETERMINING A CHANNEL STATE IN COORDINATED MULTIPOINT TRANSMISSION - In order to reduce the feedback overhead of channel state information in Coordinated Multipoint (CoMP) transmission, the present invention provides a method of determining a channel state in the CoMP transmission, wherein the serving base station receives first channel state information with the serving base station and second channel state information with each of coordinated base stations, fed back by a user equipment; informing each coordinated base stations of the corresponding second channel state information; precoding a first reference signal according to the first channel state information, and sending the precoded first reference signal to the user equipment on the communication resource commonly used with the coordinated base station, wherein the first reference signal is superimposed with precoded second reference signals respectively sent by each of coordinated base stations; receiving third channel state information fed back by the user equipment according to the superimposed reference signal, and determining a channel state of the coordinated multipoint transmission corresponding to the user equipment, according to the first, second and third channel state information. | 12-05-2013 |
20140016597 | METHOD, APPARATUS, BASE STATION AND USER EQUIPMENT FOR REDUCING INTERFERENCE IN A WIRELESS COMMUNICATION SYSTEM - A method and apparatus, a base station and user equipment for reducing interference in a wireless communication system are provide in the present invention. The wireless communication system comprises a first cell and a second cell, wherein uplink/downlink sub-frame configuration of the first cell and the second cell is asymmetry and may result in implementing a first type of sub-frame at the first cell while implementing a second type of sub-frame different from the first type of sub-frame at the second cell, thereby producing inter-cell interference. The method comprises: mapping a resource grid of at least one of the type of sub-frame and the second type of sub-frame to reserve at least one of a resource element in the first type of sub-frame and corresponding to a resource element in the second type of sub-frame and mapped for at least one of a reference signal and a common control channel, and a resource element in the second type of sub-frame and corresponding to a resource element in the first type of sub-frame and mapped for at least one of a reference signal and a common control channel, for not transmitting information; and transmitting a mapping result of the mapping step. | 01-16-2014 |
20140177492 | METHOD OF AND APPARATUS FOR INFORMING DYNAMIC UPLINK AND DOWNLINK CONFIGURATION IN HETEROGENEOUS NETWORK - The invention discloses a method and device, in a central processing unit of a control device of a pico cell or a macro cell of a heterogeneous network based upon a time division duplex system, for instructing a user equipment to perform dynamic uplink and downlink resource configuration. In the method, the central processing unit indicates whether a dynamic uplink and downlink configuration is triggered for the user equipment by using a bit reserved in broadcast channel signaling; allocates a resource of a sub frame in a frame for downlink control information in physical downlink control channel signaling when the dynamic uplink and downlink configuration is triggered for the user equipment, wherein a location of the subframe in the frame corresponds in a one-to-one manner to a dynamic uplink and downlink configuration type currently adopted for the user equipment, and the location of the sub-frame in the frame indicates a dynamic uplink and downlink configuration type currently adopted for the user equipment; and transmits the physical downlink control channel signaling including the frame to the user equipment. | 06-26-2014 |
20140177581 | METHOD OF AND APPARATUS FOR PRE-CODED PHYSICAL DOWNLINK CONTROL CHANNEL REFERENCE SIGNAL AND BLIND DECODING - The invention proposes a method of and apparatus for a pre-coded physical downlink control channel reference signal and blind decoding. In a design of the reference signal, the demodulation reference signal is used for demodulating physical downlink control channel signaling, wherein the physical downlink control channel signaling is embedded in a physical downlink shared channel, an the demodulation reference signal is included in a control channel element. In a method for a user equipment to perform blind decoding, the user equipment obtains blind decoding indication information from a base station, the blind decoding indication information including an indication of a search space in which the user equipment performs the blind decoding, wherein the search space includes a control channel element of a traditional physical downlink control channel and further includes a control channel element of a pre-coded physical downlink control channel; and performs blind decoding for the number of searches indicated by the blind decoding indication information in the search space indicated by the blind decoding indication information, according to the blind decoding indication information. | 06-26-2014 |
20140192783 | INTERFERENCE CANCELLATION METHOD AND APPARATUS FOR ENHANCED PHYSICAL DOWNLINK CONTROL CHANNEL - Embodiments of the present invention provide an interference cancellation method for an enhanced physical downlink control channel E-PDCCH, comprising steps of: (1) allocating different orthogonal covering code OCC sequences to different cells and/or different users; and (2) combining a plurality of control channel elements CCEs constituting one PDCCH with a cell-specific OCC sequence and/or a user-specific OCC sequence respectively, so as to enable a user equipment to cancel interference on the PDCCH. | 07-10-2014 |