Samsung Electro-mechanics Co., Ltd.

U Sang Lee

Sang Hyun Min

Kwang Mook Lee

Tah Joon Park

Koon Shik Cho

Sang Ho Lee

Hyung Jin Choi

Jae Hyung Lee

Joo Hyun Do

Jung Su Han

A preprocessing unit samples and digitalizes analog signal. A differential operation unit delays digitalized signal for a predetermined period and differentiates delayed signals. A correlation unit correlates differentiated signal with a plurality of predetermined PN code sequences. A setting unit includes a shift register having a plurality of storage locations for shifting the correlation values and sequentially storing shifted correlation values at the storage locations, respectively, a detector including the determination slots for detecting the storage location of the maximum value, and a slot setter for comparing the storage location of the maximum value from the detector with the predetermined reference storage location and shifting the determination slots by the difference therebetween. A demodulation value estimation unit estimates, as a demodulation value of the received analog signal, a symbol of a PN code sequence corresponding to the maximum value from the shifted determination slots.

RF receiver having timing offset recovery function and timing offset recovery method using thereof

There are provided a wireless personal area networks (WPAN) Zigbee receiver and a receiving method thereof that can obtain a spreading gain by a reduction in data rate. A wireless personal area network Zigbee receiver receiving a signal packet including a plurality of functional units having a plurality of symbols, the plurality of functional units each repeated as many as a predetermined extension number according to an aspect of the invention includes: a preamble detection unit detecting a, and generating a preamble synchronization; and an SFD synchronization unit comparing, each symbol of SFD units included in the signal packet with a predetermined SFD reference symbol continuously and repeatedly as many as the extension number, and generating an SFD synchronization signal when each of the symbols of the SFD units is equal to the SFD reference symbol as many as the extension number.

Wireless personal area network Zigbee receiver and receiving method thereof

A demodulator and a demodulating method for a WPAN are provided. In the demodulator for estimating a demodulation value of a received signal by correlating a PN code sequence of PN code having a periodic relationship for each code with a sample of the received signal, an IF processor unit separates the received signal to select only an imaginary part of the received signal, and digitalizes the selected imaginary part of the received signal. A differentiator unit delays the received signal outputted from the IF processor unit by preset delay time, and multiplies the delayed received signal by a current received signal to output a plurality of differentiated received signals. A conjugate unit sequentially stores samples of the imaginary parts of the differentiated received signals, and calculates correlation values by correcting the stored samples with PN coded sequences. A timing estimator unit receives the differentiated received signals and controls an operating timing of the conjugate unit. A demodulation value estimator unit stores the correlation values outputted from the conjugate unit and estimates the symbol of the PN code sequence corresponding to a maximum correlation value as the demodulation value of the received signal.

Demodulator and demodulating method for WPAN

The present invention relates to a multiple differential demodulator using a weighting value. The multiple differential demodulator according to the present invention includes a weighting value generator for integrating a real part and an imaginary part of a value acquired by multiplying one of a plurality of differentiated reception signals by a conjugated value of a differentiated PN code signal corresponding to a preset symbol, and determining the greater of the integrated real and integrated imaginary parts to apply a predetermined weighting value to the greater value, where the PN code signal is differentiated in the same fashion as the differentiated reception signals.

Multiple differential demodulator using weighting value

The invention relates to a symbol detector for detecting symbols received in a receive modem of short-range wireless personal area network of a ZigBee system (IEEE 802.15.4). An OQPSK short-range wireless communication system according to the invention acquires frequency offset in a received signal using a symbol contained in a preamble of a packet of the signal, multi-delay-differentiates the signal by a plurality of predetermined delay times, and complex-conjugates the acquired frequency offset to eliminate the frequency offset. Then, the OQPSK short-range wireless communication system according to the invention correlates the received signal with a PN sequence delay-differentiated through the same process to detect the symbols corresponding to the received signal.

Symbol detector based on frequency offset compensation in ZigBee system and symbol detecting method thereof

The invention relates to a receiver having a digital timing recovery function. The receiver of the invention detects frequency offset of a received signal by using symbol correlation between the received signal and a reference signal, and increases/decreases the number of data samples according to the detected frequency offset, thereby recovering symbol timing of the received signal.

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Kyungki-do, South Korea

U Sang Lee