Abstract:
The present invention relates to a geospatial information service system using a dcu of a smart grid communication network and a geospatial information service method using the same. The system includes: a smart grid communication network including power lines for transmitting power and communication signals; a plurality of DCUs installed in plurality, distributed over separate locations in middle stages of the power lines, collecting customer AMR data, and including wireless modems for wireless communication with a mobile communication terminal located within a certain range; and a geospatial information service device connected to the smart grid communication network, grasping real time location information of the mobile communication terminal on the basis of communication distances between the plurality of DCUs and the mobile communication device, and providing a spatial information service based on the location information to the mobile communication terminal. According to the present invention, for implementing an infra for providing the geospatial information service, DCUs on electric poles configuring the smart grid communication network are used without using the conventional cellular communication network or GPS. Accordingly, an economic loss can be prevented which is cased by duplicated investment for communication network facility construction, and cost can be reduced.
Abstract:
The present invention relates to a fast power line communication method which enables to efficiently allocate resource slots in a fair distribution manner on heterogeneous systems which are installed in a coexistence form on a power line by using different signals and protocols and operated to communicate; and gives priority according to the number of nodes within the heterogeneous systems, that is traffic, in order to allocate a large number of resource slots in the systems having a large amount of traffic.
Abstract:
The present invention relates to a fast power line communication method for a common signal scheme in which: an expansion of heterogeneous systems, which are newly installed and operated, is easy; a fast power line communication is possible since the coexisting homogeneous systems can always transmit/receive a signal of a fixed allocated cycle without waiting unlike previously; and meanings such as inter-node priority information are given by a sub-carrier signal transmission using not only a real area but also an imaginary area as well since the heterogeneous systems using different signals and protocols from each other communicate via a synchronization scheme using the common signal consisted of sub carriers of a frequency allocation scheme through the power line. [Reference numerals] (S110) Install a system; (S120) Participate in a common signaling; (S121) 1. Band filter method; (S122) 2. Second field usage method in time; (S130) Power line communication
Abstract:
The present invention relates to a method and apparatus for obtaining BER performance in a power line channel of a QPSK transmission method with a Nakagami noise. The present invention easily estimates a performance value.
Abstract:
본 발명에 의한 가변 고속 푸리에 변환 장치 및 그 방법이 개시된다. 본 발명에 따른 가변 고속 푸리에 변환 장치는 N개 단위로 들어오는 시간 영역의 입력 데이터에 대한 특성을 분석하고 그 분석한 결과로 그 크기가 최대값을 갖는 입력 데이터와 이에 상응하는 정밀도 비트를 출력하는 데이터 특성분석기; 상기 입력 데이터와 상기 정밀도 비트를 이용하여 FFT 연산을 수행하는 다수의 푸리에 변환 스테이지; 및 상기 FFT 연산을 수행한 주파수 영역의 출력 데이터를 주파수 순서에 맞추어 재정렬하는 출력샘플 순서 정렬기를 포함하는 것을 특징으로 한다. 이를 통해, 본 발명은 최대 성능을 보장할 수 있고, 시스템 간 상호 호환성, 및 다양한 신호해석을 지원할 수도 있다.
Abstract:
본 발명에 의해 전력선 채널에서 closed-form BER 성능을 구하기 위한 방법이 개시된다. 본 발명에 따르면 전력선 채널에서의 closed-form BER 성능을 구하는 방법은 전력선 채널 상에서 송수신되는 신호에 존재하는 배경 잡음을 구하는 단계; 상기 배경 잡음의 closed-form PDF(Probability Density Function)를 구하는 단계; 및 상기 배경 잡음의 closed-form PDF로부터 상기 송수신되는 신호의 closed-form 평균 BER 성능을 구하는 단계를 포함한다. 이를 통해, 본 발명은 성능 수치의 오차를 없앨 수 있고, 시스템의 성능을 쉽게 예측 및 분석할 수 있으며, 결과적으로 수신기의 하드웨어 설계가 용이하게 된다. 전력선 채널, 배경 잡음, BER, bit error rate, BER 성능, closed-form
Abstract:
PURPOSE: A signal transmission apparatus and a method thereof are provided to perform a stable communication by actively dealing with an abrupt channel change or a channel fading. CONSTITUTION: A data frame check sequence part(110) adds data for error detecting to a data frame offered from outside. A channel encoder(120) modulates the data frame. A symbol mapping unit(130) maps the modulated data frame to a symbol. A subcarrier availability mode(140) outputs diversity data by assigning an input data symbol to a specific subcarrier. An inverse fast fourier transformer(150) generates signals of a time domain by multiplexing phase-shifted symbols. An analog interface windowing part(160) windows the signals of the time domain for each frame. A digital analog converter(170) changes the signals of the windowed time domain into analog signals.