摘要:
A reception apparatus and method are provided for acquiring code timing by receiving pilot signals spread with allocated codes in a receiver using multiple antennas, wherein a transmitter using multiple antennas allocates different codes to pilot signals for transmitting through the respective antennas. The apparatus and method comprise receiving the spread pilot signals through the respective antennas; outputting estimated propagation delay values of the pilot signals transmitted from the respective antennas of the transmitter and peak values of matched filters for respective channels; and calculating new estimated propagation delay values by applying weights determined based on the peak values of matched filters for respective channels to the estimated propagation delay values, and acquiring code timing with the new estimated propagation delay values.
摘要:
An apparatus and for preventing a glitch in a clock switching circuit includes a select signal manager and a clock gate unit. The select signal manager generates a detect change signal, provides the detect change signal as an input signal for generating a clock gate signal to the clock gate unit, and changes a muxsel signal into a select signal using the clock gate signal to select a clock intending for switching. Upon receiving the detect change signal, the clock gate unit gates a received clock, generates the clock gate signal using a level of the detect change signal as an input signal, and provides the generated clock gate signal to the select signal manager.
摘要:
An apparatus and method for adaptively changing clock frequencies of a Central Processing Unit (CPU) and a bus in a digital system are provided. The system includes an Adaptive Frequency Scaling (AFS) controller and a clock controller. The AFS controller determines whether to change a clock frequency of the CPU according to operation information of the CPU, and determines whether to change a clock frequency of the bus according to operation information of the bus. The clock controller generates a clock frequency of the CPU and a clock frequency of the bus according to the determination of the AFS controller.
摘要:
An apparatus and method for scrambling in a wireless communication system are provided. The apparatus includes a selector, a plurality of scramblers, and a plurality of modulators. The selector selects a scrambling scheme to be applied to a transmission bit stream according to a modulation scheme to be applied to the transmission bit stream. The plurality of scramblers scramble the transmission bit stream according to a scrambling scheme corresponding to each of a plurality of modulation schemes. The plurality of modulators modulate the scrambled transmission bit stream according to the plurality of modulation schemes.
摘要:
An apparatus and method for scrambling in a wireless communication system are provided. The apparatus includes a selector, a plurality of scramblers, and a plurality of modulators. The selector selects a scrambling scheme to be applied to a transmission bit stream according to a modulation scheme to be applied to the transmission bit stream. The plurality of scramblers scramble the transmission bit stream according to a scrambling scheme corresponding to each of a plurality of modulation schemes. The plurality of modulators modulate the scrambled transmission bit stream according to the plurality of modulation schemes.
摘要:
An apparatus and method for automatically controlling a gain in a portable communication system are provided. The apparatus includes a channel determiner for controlling a fading margin depending on the channel variation amount to control the limited total dynamic range of the ADC.
摘要:
Disclosed is a method for detecting a frequency offset in an Orthogonal Frequency Division Multiplexing (OFDM) system. The method includes determining a first frequency index based on autocorrelation values calculated according to a frequency index for a pilot signal of a received symbol, accumulating the autocorrelation values calculated according to the frequency index for the pilot signal of the received symbol depending on a symbol count, and determining a second frequency index based on the accumulated autocorrelation values, and determining at least one of the first frequency index and the second frequency as a frequency offset according to channel quality.
摘要:
An apparatus and for preventing a glitch in a clock switching circuit includes a select signal manager and a clock gate unit. The select signal manager generates a detect change signal, provides the detect change signal as an input signal for generating a clock gate signal to the clock gate unit, and changes a muxsel signal into a select signal using the clock gate signal to select a clock intending for switching. Upon receiving the detect change signal, the clock gate unit gates a received clock, generates the clock gate signal using a level of the detect change signal as an input signal, and provides the generated clock gate signal to the select signal manager.
摘要:
An apparatus and method for estimating a coarse carrier frequency offset in an OFDM receiver are provided, in which an Fast Fourier Transform (FFT) unit performs FFT for a received signal over one symbol duration and outputs a previously known signal included in the FFT signal, a correlation value calculator evaluates autocorrelation values of the previously known signal for plural candidate offsets, an accumulator accumulates the autocorrelation values to the autocorrelation values evaluated over a previous symbol duration, and a maximum value selector selects first and second maximum values of the autocorrelation values. A threshold tester compares a ratio between the first and second maximum values with a predetermined threshold, and determines a candidate offset corresponding to the first maximum value as the coarse carrier frequency offset if the ratio is less than the threshold. Otherwise, the threshold tester instructs the FFT unit to receive a signal over a next symbol duration.
摘要:
Disclosed is a method for detecting a frequency offset in an Orthogonal Frequency Division Multiplexing (OFDM) system. The method includes determining a first frequency index based on autocorrelation values calculated according to a frequency index for a pilot signal of a received symbol, accumulating the autocorrelation values calculated according to the frequency index for the pilot signal of the received symbol depending on a symbol count, and determining a second frequency index based on the accumulated autocorrelation values, and determining at least one of the first frequency index and the second frequency as a frequency offset according to channel quality.