Patent application number | Description | Published |
20100141531 | POSITION TRACKING APPARATUS AND METHOD FOR A LOW POWER WPAN/WBAN DEVICE - Provided is a position tracking apparatus and method for low power WPAN/WBAN sensors in a sensor network. A position tracking apparatus collects distance information of adjacent nodes from a plurality of anchor nodes whose positions are known and at least one sensor node whose position is not known, in a sensor network, calculates the shortest path for the anchor node based on the collected distance information of the adjacent node, and classifies nodes into nodes of a first group whose positions are known and nodes of a second group whose positions are not known to select sensor nodes in an adjacent order from the second group to the first group based on the anchor node and detect the positions thereof. | 06-10-2010 |
20110268155 | DISTANCE ESTIMATION APPARATUS, SYSTEM AND METHOD USING RANGING COUNTER - Provided is a distance estimation apparatus, system and method for accurately estimating the distance between TX/RX devices by means of low-end hardware in a communication system such as the IEEE 802.15.4a system. The distance estimation apparatus includes an analog-to-digital converter, a parallelizer, a parallel synchronization means, a counter, and a system clock generator. The analog-to-digital converter analog-to-digital converts a received packet signal to generate a serial digital signal, and the parallelizer 1:N parallelizes the serial digital signal. The parallel synchronization means includes an N number of buffers for receiving the output of the parallelizer. A counter outputs a count value for estimation of the propagation delay time of a UWB signal on the basis of the sampling data retained in the parallel synchronization means. The system clock generator generates a system clock in the distance estimation apparatus. Therefore, it is possible to accurately estimate the distance between the TX/RX devices by arithmetically calculating a received signal while operating a ranging counter with a low-rate system clock, thereby simplifying the hardware structure and minimizing power consumption. | 11-03-2011 |
20130043920 | DIGITAL PHASE-LOCKED LOOP APPARATUS USING FREQUENCY SHIFT KEYING AND METHOD OF CONTROLLING THE SAME - A digital phase-locked loop apparatus using FSK includes a PFD detecting phase differences between a reference clock and a frequency-divided signal, and a first adder for generating first digital control codes by adding first digital codes, second digital codes, and channel frequency codes including channel information to each other, the first digital codes being converted from time differences between first and second pulses. The apparatus further includes a digital filter correcting errors of the first digital control codes to generate second digital control codes, a DCO for varying an oscillating frequency in accordance with a digital tuning word based on the second digital control codes, and a dual modulus division unit dividing the oscillating frequency into a frequency-divided signal. | 02-21-2013 |
20130058360 | METHOD OF GENERATING AND RECEIVING PACKETS IN LOW ENERGY CRITICAL INFRASTRUCTURE MONITORING SYSTEM - A method of generating a packet for low energy critical infrastructure monitoring (LECIM) wireless communication is provided. The method includes steps of generating a first bit string by multiplexing a physical layer header (PHR) bit and a physical layer service data unit (PSDU) bit; convolution encoding the first bit string; interleaving the convolution-encoded first bit string; generating a second bit string by multiplexing the interleaved first bit string with a synchronization header (SHR) bit; and modulating the second bit string with a frequency shift keying (FSK) method and a position-based FSK method. | 03-07-2013 |
20130070750 | METHOD AND APPARATUS FOR ACQUIRING RECEPTION SYNCHRONIZATION IN LOCAL WIRELESS COMMUNICATION SYSTEM - In a local wireless communication system, a reception signal including an STF (short training field) in which a plurality of patterns are repeatedly transmitted is received, the STF including a first number of STF patterns and a second number of STF patterns, the second number of STF patterns having an opposite code to that of the first number of STF patterns. In a first frequency offset estimation and correction process and a second frequency offset estimation and correction process, frequency offset estimation is performed on a plurality of STF patterns to acquire a phase error of each sample constituting the STF patterns, and the frequency of the STF patterns is corrected based on the acquired phase error. Cross correlation is performed on a predetermined number of STF patterns, among a plurality of STF patterns output subsequent to the frequency offset estimation and correction, to detect frame timing. | 03-21-2013 |
20130303091 | METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING HIGH FREQUENCY - A high frequency transmitting and receiving apparatus of a wireless communication system low-noise amplifies a signal that is received from a transmitting and receiving antenna through a low noise amplifier in a reception mode, and amplifies a signal be transmitted through a power amplifier in a transmission mode and transmits the signal through the transmitting and receiving antenna, and the high frequency transmitting and receiving apparatus is connected between the transmitting and receiving antenna and the low noise amplifier and turns on a switch in a reception mode and turns off the switch in a transmission mode, thereby separating transmitting and receiving signals. | 11-14-2013 |
20140016653 | METHOD OF GENERATING PACKET, METHOD OF TRANSMITTING PACKET, AND METHOD OF RANGING OF PHYSICAL LAYER TRANSMITTER OF WIRELESS PERSONAL AREA NETWORK SYSTEM - A method of generating a packet of a physical layer transmitter of a TV white space (TVWS) wireless personal area network (WPAN) system operating a WPAN service in TVWS is provided. A packet that is generated by the method of generating the packet includes a preamble, a start frame delimiter that is positioned after the preamble, a first physical layer header that is positioned after the start frame delimiter, and a physical layer service data unit that is positioned after the first physical layer header. Here, the first physical layer header represents whether the packet is a ranging packet for ranging, and includes a ranging packet identification bit corresponding to a reserved bit of the second physical layer header in a SUN system and a LECIM system, and a parity bit. | 01-16-2014 |
20140023164 | RECEIVING APPARATUS AND METHOD IN SMART UTILITY NETWORK COMMUNICATION SYSTEM - A receiving apparatus receives an FSK signal, converts the FSK signal into a phasor including amplitude and phase, estimates and compensates for a CFO (carrier frequency offset) from the converted phasor, and recovers a data bit from the converted phasor. | 01-23-2014 |
20140301412 | METHOD OF CREATING PREAMBLE, AND METHOD AND APPARATUS FOR DETECTING FRAME BOUNDARY - A method and apparatus of detecting a frame boundary by using a preamble are provided. The method includes delaying the preamble by a predetermined length of time, wherein the preamble includes an LTF and a code of the (n+1)th one of 2n sync sequences of the LTF is the inverse of a code of the last one of the sync sequences of STF; calculating a correlation value between the preamble and the delayed preamble; and detecting a frame boundary by comparing the correlation value with a threshold correlation value. | 10-09-2014 |