摘要:
Query processing system and method by query transformation transform a user request query based on an original DB structure, destined to a DBMS of a DB with some columns encrypted, into a query based on an encrypted DB structure so that the DBMS processes the query. The query is processed irrespective of whether or not the query includes an encryption-related item, and query-processing performance is remarkably improved.
摘要:
A method for transmitting a precoded signal in a collaborative multiple-input multiple-output (MIMO) communication system is described. A method for receiving a precoded signal in a MIMO communication system includes estimating, by a mobile station, channels for one or more base stations through signals received from the one or more base stations including a serving base station, transmitting precoding matrix indexes of the one or more base stations determined based on the estimated channels to the serving base station, and receiving signals precoded by the one or more base stations based on the precoding matrix index.
摘要:
Disclosed are methods of executing a handover related operation in a power saving mode in accordance with handover triggering information. One of the methods of executing handover of a mobile station in a mobile communication system comprises determining an enabled status of at least one handover related operation in a specific operation mode between the mobile station (MS) and a network, receiving control information related to the at least one handover related operation from the network, entering the specific operation mode, changing the enabled status of the at least one handover related operation in the specific operation mode, and performing the enabled handover related operation in accordance with the changed enabled status and the control information.
摘要:
A method of transmitting data using a generalized phase shift based proceding or an extended phase shift precoding scheme in a multiple-antenna system using a plurality of subcarrier and a transceiver for supporting the same are disclosed. A phase shift based precoding matrix may be generalized and determined by a product of a diagonal matrix for phase shift and a unitary matrix for maintaining orthogonality in spatial domain. The diagonal matrix may be extended by a product of a proceding matrix for increasing channel power and the diagonal matrix for phase shift. The design of the transceiver can be simplified or communication efficiency can be improved by generalizing and extending the phase shift based proceding.
摘要:
According to one embodiment, a method for repetitive transmission using a plurality of sub-carriers includes: preparing a symbol to be transmitted using the plurality of sub-carriers within a single time domain unit; repeating the symbol a predetermined number (N) of times; applying a corresponding one of N different cyclic shift values to each of the N repeated symbols to be transmitted using the plurality of sub-carriers within the single time domain unit; performing an IFFT (Inverse Fast Fourier Transform) on each of the N repeated symbols to which the corresponding one of the N different cyclic shift values is applied; and transmitting the N repeated symbols on which the IFFT is performed using the plurality of sub-carriers.
摘要:
Query processing system and method by query transformation transform a user request query based on an original DB structure, destined to a DBMS of a DB with some columns encrypted, into a query based on an encrypted DB structure so that the DBMS processes the query. The query is processed irrespective of whether or not the query includes an encryption-related item, and query-processing performance is remarkably improved.
摘要:
A phase-shift based pre-coding scheme used in a transmitting side and a receiving side that has less complexity than those of a space-time coding scheme, that can support various spatial multiplexing rates while maintaining the advantages of the phase-shift diversity scheme, that has less channel sensitivity than that of the pre-coding scheme, and that only requires a low capacity codebook is provided.
摘要:
A method of transmitting pilot symbols is disclosed. In a communication system performing communications using a plurality of antennas and multiple carriers, the present invention includes the steps of generating a plurality of pilot symbol sequences based on a basic code sequence, data-processing a plurality of the pilot symbol sequences by allocating each of a plurality of the pilot symbol sequences to the multiple carriers, and transmitting each of a plurality of the data-processed pilot symbol sequences via a corresponding one of a plurality of the antennas.
摘要:
Methods of controlling a transmission power and configuring a codebook in a multi-antenna system to solve a transmission power unbalance between antennas are disclosed. The method of transmitting data in a multi-antenna system includes (A) transmitting one or more pilot signals within a first symbol region through a first antenna unit, and (B) transmitting one or more pilot signals within a second symbol region through a second antenna unit, wherein data within the first symbol region is transmitted through the second antenna unit, and data within the second symbol region is transmitted through the first antenna unit. According to the present invention, since a transmission power unbalance between antennas is solved, a transmission power can be uniformly assigned to each antenna and channel estimation can be easily performed. Moreover, a power amplifier having a uniform amplification range can be used and designed.
摘要:
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.