Abstract: Provided are a signal amplifying apparatus and method and a wireless transmitter using the same. The signal amplifier includes a polar coordinate converter configured to output an envelope signal and a phase signal by converting a signal to a polar coordinate, a multilevel quantizer configured to output a multilevel quantized signal by quantizing the envelope signal to multiple levels, an amplification state controller configured to control an amplification state using the multilevel quantized signal, and a power amplifier configured to amplify the phase signal according to the controlled amplification state.

Abstract: A system for synchronization of an orthogonal frequency division multiplexing signal having a first frequency. The system includes filters configured to receive the OFDM signal, and output second signals corresponding to different frequency bands of the OFDM signal. Each of the second signals includes a corresponding synchronization symbol associated with the OFDM signal, and the synchronization symbols of each of the second signals are the same. The system further includes a Fourier transform circuit configured to receive the second signals from the filters, and output the second signals. Each of the second signals has a second frequency. The system is configured to detect the synchronization symbols in the second signals, and detect a start of OFDM symbols in the OFDM signal based on the detected synchronization symbols. The start of the OFDM symbols corresponds to an average of a plurality of estimations of the start of the OFDM symbols.

Abstract: A system and method provides adaptive digital front end control of an incoming radio frequency (RF) signal to identify RF characteristics in that signal, such as interference or desired data signals and adaptively control digital filter elements to selectively tune only portions of the RF signal to produce a filtered output signal, on a per cycle basis, prior to communicating the RF signal to an underlying wireless communication device, such as a base station in cellular network, cellular phone, wireless router base station, cognitive radio, or other wireless communication device. Each digital filter element may be tuned in frequency and bandwidth of operation and collectively the elements form an adaptive filter stage with elements configurable into both bandpass and bandstop filters for cascaded operation.

Abstract: In a communications system, transmitter power gain can be changed between symbols. A power gain change of a first part of a transmit chain is initiated a first time, whereas a power gain change of a second part of the transmit chain is initiated at a second time, such that the resulting power gain changes of the first and second parts both occur substantially within an inter-symbol time in a desired relationship to one another. In one example, the power gain change of the first part is initiated before the beginning of the inter-symbol time to account for expected serial bus latency between initiation and execution of the power gain change of the first part. The power gain change of the second part is initiated during the inter-symbol time such that overall power does not exceed an amount (for example, a maximum permitted under a communication standard).

Abstract: Embodiments describe a method of measuring noise and interference within transceivers of an OFDM wireless transmission system, or similar communication system, including a number of receivers communicating with one or more base stations in cell or sector arrangements. The transmitter schedules a transmission burst for a non-existent user (receiver) using wireless transmission traffic. In an OFDM system, this corresponds to a certain set of subcarriers in the time/frequency arrangement. Thus, in the receive frame structure, the data and pilot subcarriers are guaranteed to be only noise and interference from adjacent sectors. The receiver can accurately measure the noise and interference without needing to cancel out the transmitted signal. Therefore, the system is assured that there is no desired signal as part of this measurement. The noise and interference measurement process can be appropriately scheduled so that it does not impact the overall throughput of the system.

Abstract: A system and method are disclosed to synchronize adaptively a transform window in a multiple sub-carrier communication system based on analysis of a time domain channel impulse response. A set of frequency domain channel estimates, derived from received and one-dimensional Wiener filter interpolated channel estimates, are transformed into a time domain channel impulse response estimate containing multiple, repeated constituent responses. Each order of the constituent responses in the time domain channel impulse response estimate is associated with a two-dimensional Wiener interpolation filter. The set of two-dimensional Wiener interpolation filters generate interpolated channel estimates to compare with received channel estimates to determine a best channel impulse response order of the constituent responses. The transform window is adaptively updated using the best channel impulse response order.

Abstract: A transmitter comprises a channel encoder to encode data bits; a modulator to modulate the encoded data bits, wherein the modulator selects one of a first modulation scheme and a second modulation scheme for each of a plurality of time slots; wherein, for each time slot, the channel encoder: includes a prefix and a suffix at the beginning and end, respectively, of the encoded data bits corresponding to the respective time slot, the prefix and the suffix being selected based on the selected modulation scheme for the respective time slot; and passes the prefix, the encoded data bits, and the suffix to the modulator; wherein, for each time slot, the modulator: modulates the prefix, the encoded data bits, and the suffix received from the channel encoder according to the selected modulation scheme for the respective time slot; and applies a window function to the prefix and the suffix.

Abstract: A semiconductor memory device stably performs a read operation at a high frequency, thereby reducing a current consumption. The semiconductor memory device is capable of performing the read operation stably by controlling a data eye. The semiconductor memory device includes an output unit and a data eye control unit. The output unit outputs data in synchronization with clock signals. The data eye control unit controls a data eye of the data output by the output unit.

Abstract: Method and apparatus for generating ternary and multi-valued Gold sequences, are disclosed. Also methods to detect ternary and multi-valued sequences are disclosed. The detection can be performed by a ternary or multi-valued LFSR descrambler when the sequences are generated by an LFSR based sequence generator. A wireless system which can assign additional sequences to designated users is also disclosed. The wireless system can also transfer information to user equipment that enables methods for sequence generation and sequence detection.

Abstract: A transmission device of the present invention includes a MAC that generates data I transmitted by a band group M and generates data J transmitted by a band group N; signal switching parts that exchange a part of the data I and a part of the data J; and antennas that simultaneously transmit the data I and the data J after data exchange is performed by the signal switching parts, by the band group M and the band group N.

Abstract: Embodiments of a wireless transceiver are provided. Embodiments can be used in multiple-input-multiple-output (MIMO) wireless transceivers. In an embodiment, radio control signal bundles are provided as direct parallel interconnects between digital signal processing modules and the radio module of the wireless transceiver to enable a precise low-latency control of radio functions. In another embodiment, a separate physical line is provided to control each radio setting of the radio module, thereby enabling simultaneous real-time control of any number of radio settings. In a further embodiment, the various digital and analog components of the wireless transceiver are integrated within a single chip of the same process technology.

Abstract: In one embodiment, a method includes receiving a carrier signal transmitted by a base station according to either a first data-transmission protocol or a second data-transmission protocol; detecting a first field gap in the carrier signal indicating initiation of a data transmission by the base station; and determining whether a reference duration is present in the carrier signal after the first field gap. The method includes, if the reference duration is present in the carrier signal after the first field gap then, according to the first data-transmission protocol, determining a calibration value for the data transmission based on the reference duration and decoding the data transmission by measuring durations between successive subsequent field gaps and determining whether each duration as measured is a binary 1 or binary 0 based on the calibration value.

Abstract: An apparatus and method for transmitting/receiving a reference signal in a communication system are provided, in which a transmitter determines first and second different transmit power values for first and second pilot tones residing in one of the substantially same time resource and the substantially same frequency resource among pilot tones included in a data area in a subframe having time and frequency resources, and transmits the first pilot tone with the first transmit power value and the second pilot tone with the second transmit power value. The first transmit power may be a reference transmit power value and the second transmit power may be a product between a weight and the reference transmit power value.

Abstract: There is disclosed a general-purpose APD measurement apparatus capable of changing a measurement condition, such as the number of channels or a resolution bandwidth (RBW) in compliance with a standard for the subject of measurement, measuring various subjects of measurement, and correcting measurement equipment, thereby enabling a higher accuracy of measurement. The resolution bandwidth (RBW) or the number of channels when measurement is performed can be flexibly changed by controlling the cycle of a clock signal whose data are sampled by A/D conversion means 110, frequency selection means 130, and an APD unit 300. The frequency selection means 130 includes FFT type processing means 131 and filter bank type processing means 132 arranged in parallel. The output of FFT type processing means 131 is corrected based on the output of the filter bank type processing means 132 with a high accuracy of measurement. Accordingly, a higher accuracy of measurement is made possible.

Abstract: An exemplary method is disclosed to accurately estimate the center frequency of a narrow-band interference (NBI). The exemplary method uses multi-stage autocorrelation-function (ACF) to estimate an NBI frequency. The exemplary method allows an accurate estimation of the center frequency of NBI in an Ultra-Wideband system. A narrow band interference (NBI) estimator based on such a method allows a low complexity hardware implementation. The exemplary method estimates the frequency in multiple stages. Each stage performs an ACF operation on the received signals. The first stage gives an initial estimation and the following stages refine the estimation. The results of all stages are combined to produce the final estimation. An apparatus based on such a multi-stage narrow band interference frequency detector is also disclosed to improve the accuracy by combining various filters with the detector.

Abstract: A method and apparatus for transmitting signals in a multi-hop wireless communication system are provided. A first BS transmits a signal including a first common information codeword and a first private information codeword. A second BS transmits a signal including a second common information codeword and a second private information codeword. A first RS joint-decodes the first common information codeword and the second common information codeword and decodes the first private information codeword. A second RS joint-decodes the first common information codeword and the second common information codeword and decodes the second private information codeword.

Abstract: A mechanism for weak signal packet detection in a wireless receiver. Cross-correlation and self-correlation operations are performed on a plurality of short training field symbols associated with a plurality of RF signals received at a plurality of receiver chains of the wireless receiver. A plurality of self-correlation outputs generated in the plurality of receiver chains are summed and the sum of the self-correlation outputs is accumulated over a predetermined number of STF symbol periods. A moving sum operation is performed on the accumulation output when the accumulation output is greater than a first predetermined threshold. A signal indicating a data packet has been detected is generated when the moving sum output is greater than a second predetermined threshold.

Abstract: There is a need for reducing the scale of a circuit that determines and decodes code types for reception signals coded with different codes. A reception logic circuit determines and decodes code types for reception signals coded with different codes. The reception logic circuit determines one of code types for a demodulation signal corresponding to the reception signal based on a difference between codes detected during a modulation period or a non-modulation period occurring in the demodulation signal. The reception logic circuit decodes the code type in accordance with the determined code type based on the modulation period or the non-modulation period that alternately occurs in the demodulation signal. In this manner, the received data is reproduced. There is no need for a decoder specific to each code.

Abstract: A TFI-OFDM transmission system for a UWB communication that includes a data generator generating data having a rate corresponding to a transmission speed mode, a convolutional encoder convolutional-encoding the data into a certain number of data groups, an OFDM modulator outputting OFDM symbols by executing an IFFT the data groups a buffer temporarily storing the OFDM symbols to sequentially transmit the OFDM symbols in a time domain at least two times, and a frequency generator generating certain frequencies to transmit the OFDM symbols in a certain number of frequency bands corresponding to transmission channels.

Abstract: A method and apparatus that allows egress pointer smoothing data by evaluating the average fill of an elastic store. For one embodiment of the invention, an elastic store implements a plurality of independent FIFOs, each FIFO having a write pointer and a read pointer, the write pointer including a marking pointer field and valid flag field. An incoming byte is received to a location within a traffic memory and the write pointer is used to instruct the traffic memory to indicate that the incoming bit has been received to the location. The valid flag field is set to indicate that the value at the location is currently valid.