摘要:
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.
摘要:
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.
摘要:
Provided are an apparatus and method for allocating resources in a mobile communication system. The apparatus includes a modulating/coding unit for modulating transmission data of one or more users according to a predetermined modulation scheme and for outputting a complex signal; a 2-Dimensional (2D)/1-Dimensional (1D) converter for converting the complex signal into a 1D signal; and a re-modulator for reconstructing the 1D signal to a 2D signal and for allocating two components of the 2D signal to two different frequency bands.
摘要:
Provided are an apparatus and method for allocating resources in a mobile communication system. The apparatus includes a modulating/coding unit for modulating transmission data of one or more users according to a predetermined modulation scheme and for outputting a complex signal; a 2-Dimensional (2D)/1-Dimensional (1D) converter for converting the complex signal into a 1D signal; and a re-modulator for reconstructing the 1D signal to a 2D signal and for allocating two components of the 2D signal to two different frequency bands.
摘要:
A synchronization method in an OFDM based communication system. A transmitting side generates and transmits an OFDM symbol having a constant cyclic prefix, independent of time domain data symbols that are to be transmitted. A receiving side estimates a timing synchronization error based on the known cyclic prefix. Because the timing synchronization error is estimated based on the constant cyclic prefix, which is always known, a highly reliable correlation is achieved, thereby improving the accuracy of synchronization.
摘要:
A phase-change random access memory device is provided. The phase-change random access memory device includes a global bit line connected to a write circuit and a read circuit, multiple local bit lines, each being connected to multiple phase-change memory cells, and multiple column select transistors selectively connecting the global bit line with each of the multiple local bit lines, each column select transistor having a resistance that varies depending on its distance from the write circuit and the read circuit.
摘要:
Provided are a receiver and a method for detecting a signal in a multiple antenna system. The receiver includes a filter coefficient calculator and a signal detector. After separating a first signal portion and a second signal portion, the filter coefficient calculator calculates an MMSE filter coefficient using a Matrix Inversion Lemma such that an inverse matrix of the first signal portion has a predetermined constant value regardless of a repetition signal detection process. The signal detector detects a relevant transmission signal from an interference-removed reception signal using the MMSE filter coefficient.
摘要:
A phase change memory device includes a memory cell having a phase change material, a write driver which supplies a step-down set current to the memory cell, where the step-down set current includes a plurality of successive steps of decreasing current magnitude, and a set program control circuit which controls a duration of the step-down set current supplied by the write driver.
摘要:
A variable resistance memory device includes a memory cell array having a plurality of memory cells, a write driver which supplies a step-down set current to the memory cells, where the step-down set current includes a plurality of successive steps of decreasing current magnitude, and a set program control circuit which controls a duration of the step-down set current supplied by the write driver. The set program control circuit controls the duration of the step-down set current in accordance with at least one of data contained in an mode register set (MRS) and a conductive state of a fuse element.
摘要:
A phase change memory device is provided which includes a memory cell array including a plurality of memory cells, and a write driver for supplying a program current to the memory cell array through a global bitline. The memory cell array includes first and second cell regions, a first local bitline connected to the first cell region, a second local bitline connected to the second cell region, and a select region disposed between the first and second cell regions and supplying the program current supplied through the global bitline to the first and second local bitlines in response to a local select signal.