摘要:
A PPB-CM communication system and method. The PPB-CM communication system includes a transmitter which splits a symbol period, which is a transmission unit of a communication signal, into at least a pair of parts, inserts a data signal into one of the parts, and transmits a communication signal having the data signal inserted; and a receiver which receives the communication signal from the transmitter and determines bit information of the symbol period according to which part of the symbol period has the data signal inserted, as determined by comparison of energy levels of the parts. Accordingly, a separate threshold is not required to determine the data bit of the symbol period. Thus, the communication signal can be accurately determined. Also, the communication system can be simply implemented without need of a delay line.
摘要:
Provided is an apparatus and a method of measuring a distance between devices using a low clock frequency signal. The apparatus includes clock frequency generators, counters, a controller and a calculator for determining the distance based on clock signal overlap. Radio waves are transmitted and a number of clocks of a clock signal having a clock frequency b are counted, and if the transmitted radio waves are received again, a number of clocks of a clock signal having a clock frequency a are counted. If the clock signals having the clock frequencies a and b overlap with each other, counting of the numbers of the clocks of the clock signals having the frequencies b and a stops, and the distance is measured using the count values of the clock signals having the clock frequencies a and b. As a result, number of clocks of clock signals having low clock frequencies with a uniform difference can be counted to precisely measure a distance.
摘要:
Provided is an apparatus and a method of measuring a distance between devices using a low clock frequency signal. The apparatus includes clock frequency generators, counters, a controller and a calculator for determining the distance based on clock signal overlap. Radio waves are transmitted and a number of clocks of a clock signal having a clock frequency b are counted, and if the transmitted radio waves are received again, a number of clocks of a clock signal having a clock frequency a are counted. If the clock signals having the clock frequencies a and b overlap with each other, counting of the numbers of the clocks of the clock signals having the frequencies b and a stops, and the distance is measured using the count values of the clock signals having the clock frequencies a and b. As a result, number of clocks of clock signals having low clock frequencies with a uniform difference can be counted to precisely measure a distance.
摘要:
A radio frequency (RF) communication system having a chaotic signal generator and a method of generating a chaotic signal. The RF communication system includes a chaotic signal generator which generates a chaotic signal having a plurality of frequency components at a predetermined frequency band, a modulator which generates a chaotic carrier by combining the chaotic signal with a data signal which indicates information, and a transmission circuit which includes an antenna to transmit the chaotic carrier made at the modulator. The frequency signal generator comprises an oscillator which converts a DC bias power into a high frequency power, and a resonating unit which generates a wideband signal having a plurality of frequency components by passing a predetermined frequency band of the high frequency power signal.
摘要:
A wireless communication system and a method for reducing a ranging time. The communication system includes a main synchronization block group which processes the transceived signal and determines whether the transceived signal is a signal desired by a transmitting device when a receiving device re-transmits the transceived signal to the transmitting device; a ranging block which measures a distance between the transmitting device and the receiving device using a ranging signal when the transceived signal is the desired signal of the transmitting device based on the determination of the main synchronization block group and when the transceived signal is the ranging signal; and a symbol synchronization block which detects a start point and an end point of a symbol forming the signal when the transceived signal from the receiving device is a data communication signal. Accordingly, the fast ranging is feasible and channel occupation time can be shortened.
摘要:
A communication system which transmits and receives a communication signal having an intra-guard-interval (IGI) inserted is provided. The communication system includes a signal generator which is configured to generate a signal to carry data; and a signal output part which is configured to split a symbol period, which is a transmission unit of the communication signal into a plurality of sections, and to selectively insert the signal which is generated into the plurality of sections, and to output the communication signal.
摘要:
A method and apparatus for simplifying a structure needed to delay data in delay units when a reference signal and data are transmitted by using chaotic signals are provided. The method includes delaying data by at least two delay times, wherein each of the delay times occurs sequentially; multiplexing the data, which has been delayed, according to a control signal; and transmitting the data and a reference signal which corresponds to the data at an interval of delay time. The apparatus includes a first delay unit which is configured to delay data for a first delay time; a second delay unit which is configured to delay the data output from the first delay unit for a second delay time; and a multiplexer which is configured to multiplex the data from the first and second delay units according to a control signal.
摘要:
RF (radio frequency) communication devices which use a chaotic signal and a method thereof are provided. An RF communication system includes: a transmitter terminal which generates a chaotic signal including a plurality of frequency components in a predetermined frequency band and transmits a chaotic carrier generated by inserting a data signal including information to be transmitted into the chaotic signal to a receiver terminal; and the receiver terminal extracts the data signal from the chaotic carrier received from the transmitter terminal via a wireless network and outputs the extracted data signal. As a result, low power, light weight local area RF communication devices can be realized.
摘要:
A wireless communication system and a method for reducing a ranging time. The communication system includes a main synchronization block group which processes the transceived signal and determines whether the transceived signal is a signal desired by a transmitting device when a receiving device re-transmits the transceived signal to the transmitting device; a ranging block which measures a distance between the transmitting device and the receiving device using a ranging signal when the transceived signal is the desired signal of the transmitting device based on the determination of the main synchronization block group and when the transceived signal is the ranging signal; and a symbol synchronization block which detects a start point and an end point of a symbol forming the signal when the transceived signal from the receiving device is a data communication signal. Accordingly, the fast ranging is feasible and channel occupation time can be shortened.
摘要:
A communication system includes a transmitter having a signal generator for generating a signal for transmitting data, a transmission delay unit for repeatedly delaying the signal from the signal generator for a predetermined delay time within a symbol period and generating corresponding delayed signals, and a selector for selectively providing one of the delayed signals from the transmission delay unit to an antenna; and a receiver having a reception delay unit for receiving the signal from the transmitter and delaying the signal as long as the delay time of the transmission delay unit, and a data judgment block for discriminating data bits of the signal from the transmitter by comparing the signal from the transmitter with the delayed signal from the reception delay unit. According to the communication system, the delay time can be accurately adjusted even if the delay line is shortened, and the data bits of the communication signal can be accurately judged in the receiver side.