Abstract:
A method for triggering multicell MIMO schemes in a multiple antenna system includes transmitting, at a Mobile Station (MS), a first feedback information for single-cell closed-loop MIMO to a Base Station (BS); requesting, at the BS, Normalized Interference Power (NIP) feedback from the MS based on the first feedback information; feeding, at the MS, the NIP back to the BS; selecting, at the BS, a first NIP threshold and a second NIP threshold based on the NIP fed back from the MS; and requesting, at the MS, one of a first MIMO scheme and a second MIMO scheme by comparing the calculated first and second NIPs with the first NIP threshold and the second NIP threshold.
Abstract:
An apparatus and a method for operating a Mobile Station (MS) in a wireless communication system are provided. The method includes receiving a threshold for a gap of an average Receive (Rx) power between a neighboring Base Station (BS) and a serving BS, transmitting to the serving BS, identification information of a BS having the average power greater than a first value, receiving information of a BS involving joint processing generated using information of the BS having the average power greater than the first value, feeding Precoding Matrix Index (PMI) information of the BS involving the joint processing, back to the serving BS, receiving information indicating a PMI operation mode of the MS, from the serving BS, and determining a PMI operation mode according to the information indicating the PMI operation mode of the MS.
Abstract:
A communication apparatus and method in a wireless communication system that support multiple Orthogonal Frequency Division Multiplexing (OFDM) parameter sets. A method includes determining a respective OFDM parameter set for each of multiple Radio Frequency (RF) chains; and processing an OFDM signal in each of the multiple RF chains based on a parameter value defined in the respective OFDM parameter set.
Abstract:
A method and apparatus reduce overhead of feedback in a closed loop Multiple Input Multiple Output (MIMO) system. A controller feeds back the long-term Precoder Matrix Index (PMI) to a serving base station under direction of the serving base station when the long term PMI feedback transmission is required, generates a new codebook using the long term PMI, and determines a short term PMI from the new codebook. A feedback transmitter feeds back the short-term PMI to the serving base station.
Abstract:
A method for operating a Mobile Station (MS) in a Multiple Input Multiple Output (MIMO) wireless communication system is provided. The method includes measuring channel quality for a serving Base Station (BS), if the channel quality is less than a threshold, measuring interference power from one or more neighbor BSs, determining a Precoding Matrix Index (PMI) and a priority metric for each neighbor BS, and feeding back at least one of the PMI, a PMI type indicator, the priority metric, and the channel quality to the serving BS.
Abstract:
A method provides mixed analog/digital beamforming by a transmitter in a mobile communication system. The method includes converting a modulation symbol into a parallel symbol stream, performing digital beamforming on the parallel symbol stream, performing an IFFT operation on the digital-beamformed parallel symbol stream to generate a time-domain symbol, converting the IFFT-operated time-domain symbol into a serial time-domain symbol, inserting a CP into the serial time-domain symbol, performing a DAC operation on the CP-inserted symbol to generate an analog signal, and performing analog beamforming by multiplying the analog signal by the analog beamforming precoder optimized for the first subcarrier transmitted through at least one RF channel.
Abstract:
Provided is a device and a method for eliminating inter-cell interference in Multiple Input Multiple Output (MIMO) wireless communication system. The method for operating a user equipment for eliminating the inter-cell interference includes determining one or more optimum bands among bands not requested to be restricted from a neighboring cell, determining at least one of band and Precoding Matrix Index (PMI) to be requested to be restricted to the neighboring cell among the determined one or more optimum bands, and feeding back at least one of the band and PMI to be requested to be restricted to the neighboring cell to a serving base station.
Abstract:
A Mobile Station (MS) apparatus and a Base Station (BS) apparatus, and methods for their operation in a wireless communication system, are provided. The method for operating the MS includes receiving Precoding Matrix Index (PMI) subset information from a BS, determining downlink channel quality of the BS, determining a PMI for the BS based on the PMI subset information and the determined downlink channel quality of the BS, and transmitting the determined PMI to the BS.
Abstract:
A multiple antenna system including a mobile station and a base station are operable to perform a method for transmitting control information for interference mitigation. A Mobile Station (MS) can transmit control information for interference mitigation. The MS determines a first Precoding Matrix Index (PMI) and a second PMI for interference from an adjacent Base Station (BS). Based on a correlation level from correlation values between one of the first PMI and second PMI and the remaining PMIs in the codebook, the MS determines a level of a subset of PMIs, and feeds back information indicating the correlation level.
Abstract:
Disclosed is a system and a method for performing handover in a Worldwide interoperability for Microwave Access (WiMAX) mobile communication system supporting broadband wireless access. The system includes a plurality of Mobile Stations (MSs); at least one distributed antenna having the ability to perform simultaneous communications with the plurality of MSs; and a base station connected to the at least one distributed antenna through optical fibers for performing communications and handovers with the multiple MSs.