Electronics and Telecommunications Research Institute

Korea Telecom

Ik Soo Eo

Hyun Kyu Yu

Sang-Kyun Kim

Jang Hong Choi

Hee Bum Jung

Tae Joon Kim

Kyung Soo Kim

Bon Tae Koo

Cheon Soo Kim

Mi Jeong Park

Seon-Ho Han

Kwang Il Yeon

Hyoun Kuk Kim

In Gi Lim

Young Hoon Kim

Jung Bum Kim

Min Sang Park

Kyung Jin Byun

Mun Yang Park

Sang Kyun Kim

Pil Jae Park

In San Jeon

Seon Ho Han

Hyun Cheol Park

Hyun Chul Park

Hyun Ho Boo

YoungSeok Baek

Mijeong Park

Provided is a fast Fourier transform device for analyzing specific frequency components of an input signal. The fast Fourier transform device includes an address generator that generates an address, based on a first frequency index corresponding to a first frequency, an FFT coefficient table that outputs a first Fourier transform coefficient corresponding to the generated address among Fourier transform coefficients of the first frequency index, and an operator that calculates a frequency characteristic of an input signal associated with the first frequency, based on the input signal and the first Fourier transform coefficient.

Fast Fourier transform device for analyzing specific frequency components of input signal

Provided is a narrow-band radar device including an orthogonal code generator configured to generate a plurality of orthogonal generators, a pseudo-noise code generator configured to generate a plurality of pseudo-noise codes, a radar transmitter configured to spread-modulate transmission data using the plurality of orthogonal codes and pseudo-noise codes, and a radar receiver configured to demodulate a reception signal using the plurality of orthogonal codes and pseudo-noise codes, and calculate at least one of an azimuth angle, elevation angel, speed, or range of a target from the demodulated reception signal.

Narrow-band radar device and operation method thereof

A method and device for calibrating a DC offset and an I-Q imbalance component of an RF transceiver, the method including inputting a test signal into a transmitter, and converting the test signal into an analogue test signal; converting the analogue test signal using a transmitting mixer; sub-sampling a signal output from the transmitting mixer; and computing a DC offset calibrating constant number and an I-Q imbalance calibrating constant number from a sub-sampled signal.

Method and device for calibrating IQ imbalance and DC offset of RF tranceiver

Disclosed is an interpolation filter based on time assignment algorithm. An interpolation filter comprises an enable signal generating part generating enable signals for operation of the interpolation filter, an input value generating part generating input values, a first calculating part generating a first output value based on a first enable signal and a first input value, a second calculating part generating a second output value based on a second enable signal and a second input value, and an output value selecting part selecting a final output value among the first output value and the second output value. Thus, continuity of output data can be guaranteed, and hardware can be shared by using time assignment algorithm so that a total size of the interpolation filter can be reduced.

Interpolation filter based on time assignment algorithm

A digital RF receiver does not use a separate receiver according to a mode and a band for multi-mode reception, MIMO reception, and bandwidth extension reception, and changes only setting variables in a single receiver structure so as to implement multi-mode reception, MIMO reception, bandwidth extension reception, and/or simultaneous multi-mode operation, such that complexity of the receiver, development cost, and power consumption can be reduced.

Digital radio frequency (RF) receiver

The present invention relates to a single frequency synthesizer based FDD transceiver. A single frequency synthesizer generates and provides a carrier frequency so that frequency up-conversion and frequency down-conversion can be performed at the time of transmission and reception. Accordingly, the area, power consumption, and design complexity of the entire system can be reduced, and the performance of the system can be improved.

Single frequency synthesizer based FDD transceiver

Embodiments provide a digital RF receiver including a signal converting unit which converts an RF signal received from an external device into a digital signal, a plurality of functional modules which processes the digital signal in accordance with a predetermined algorithm when the digital signal is input, and a signal processing controller which selects at least one of the plurality of functional modules to control the digital signal to be processed in consideration of whether an IF signal component is included in the digital signal or a sampling rate related with sampling information of the digital signal.

Digital RF receiver

An embodiment of the present invention relates to a radar apparatus, wherein a distance to a target and a velocity of the target are measured by transmitting a digitally modulated transmitting signal using a digital code and receiving and demodulating an echo signal returned due to reflection of the transmitting signal from the target.

Radar apparatus

A data rate conversion device generates a first parameter representing a memory address position to sample and a second parameter representing a phase value of an estimation time point, records input data at a memory based on an input clock, outputs sampled continued data from the memory using the first parameter based on an output clock, and generates and outputs final data using the continued data, a plurality of filter coefficients, and the second parameter.

Device and method for converting data rate

The present invention relates to a digital front end receiver using a DC offset compensation scheme. The digital front end receiver includes a DC offset compensation filter configured to remove DC offset components from signals received from a digital mixer and a Cascaded Integrator-Comb (CIC) decimation filter configured to reduce a sampling rate of the signals received from the DC offset compensation block.

Digital front end receiver using DC offset compensation scheme

Disclosed is a method for receiving an analog signal from a receiver supporting at least a first channel band and a second channel band. The method for receiving an analog signal includes sampling the analog signal received through an antenna, generating a decimated signal by passing the sampled signal to a CIC decimation filter; and inputting the decimated signal to a channel selection filter.

Signal receiver with digital front end supporting multiple band and signal receiving method using the same

Provided are a multiplierless FIR digital filter and a method of designing the same, in which a filtering operation is performed by a small addition/subtraction circuit using extracted information after analyzing the property of a given coefficient and extracting information required for design by only adding/subtracting operations. In the method of designing the multiplierless FIR digital filter, tables are created to extract and store information needed for adding and subtracting operations. An addition table is created to store values obtained by adding the input data synchronized with a clock frequency. Further, a value corresponding to multiplication is obtained by performing extraction and error correction on the added values from the tables, and an adder chain of an output terminal sums up the values and outputs the filtering results, thereby effectively implementing a logic circuit of the multipliedess FIR digital filter.

Multiplierless FIR digital filter and method of designing the same

A method for stable channel estimation to increase frequency band efficiency that is lost by using a pilot, and to reduce the complexity and the sensitivity to channel zero. The method includes generating an i-th symbol block Sincluding N carriers, performing an inverse fast Fourier transform (IFFT) operation on the i-th symbol block, and forming an orthogonal frequency division multiplexing (OFDM) symbol block. The method also includes attaching a guard interval sample in front of the i-th OFDM symbol block Uand forming at least one OFDM symbol block U. The method further includes modeling the formed OFDM symbol block Uwith a channel finite impulse response (FIR) filter and estimating channel impulse response using signals yi received through a channel.

Blind channel estimation in an orthogonal frequency division multiplexing system

Provided is a method for converting a dimension of a vector. The vector dimension conversion method for vector quantization includes the steps of: extracting a specific parameter having a pitch period from an input speech signal and then generating a vector of a dimension that varies according to the pitch period; dividing an entire frequency domain of the generated vector of the variable dimension into at least two frequency domains; and converting the vector of the variable dimension into vectors of mutually different fixed dimensions according to the divided frequency domains. Thereby, not only an error due to the vector dimension conversion is suppressed but codebook memory required for the vector quantization is effectively reduced.

Method for reducing decoder complexity in waveform interpolation speech decoding by converting dimension of vector

Provided is a receiver of a multi-input multi-output system using multiple antennas, the receiver including: a first multiplying unit for multiplying a vector r received via the antenna by a Hermitian matrix Q; a candidate transmitting vector generating unit for detecting a signal on a lowest modulation order transmitting antenna from the received vector y output from the first multiplying unit, creating as many symbol candidates as the modulation order of the detected signal, and generating a candidate transmitting vector using each symbol candidate; a transmitting vector determining unit for obtaining a distance between each candidate transmitting vector generated by the candidate transmitting vector generating unit and the received vector y to determine a final transmitting vector; and a demodulating unit for demodulating the final transmitting vector determined by the transmitting vector determining unit. Since the receiver detects a transmitting vector with reference to a signal on a lowest modulation order transmitting antenna, the receiver can have a simpler structure.

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Daejeon, South Korea

Ik Soo Eo