Abstract:
PURPOSE: A clock group monitoring and selecting circuit is provided to simultaneously receive two clock groups from external clock boards, and to monitor whether the two clock groups are normal, then to supply a normal clock group to a modem, thereby stabilizing clocks distributed to the system modem. CONSTITUTION: The first and second clock receivers(110,120) receive the first and second clock groups consisting of many clocks from external clock boards. The first and second clock monitors(210,220) check states of the received first and second clock groups, respectively, and output result signals. A clock selector(300) selects the received first and second clock groups according to outputted state monitor information of the first and second clock groups, and outputs the selected clock groups. The first and second clock monitors(210,220) include retriggerable monostable multi-vibrators as many as the number of clocks included in the first and second clock groups. The retriggerable monostable multi-vibrators monitor the clock groups, and generate high-level signals if the clock groups are not inputted, then generate low-level signals if the groups are inputted.
Abstract:
본 발명은 버터플라이 장치 및 이를 이용한 고속 퓨리에 변환 연산 시스템에 관한 것이다. 본 발명의 고속 퓨리에 변환 연산 시스템은 입력 데이터에 대하여 가변적인 값을 갖는 래딕스(RADIX) 버터플라이 연산을 수행하는 가변 래딕스(RADIX) 버터플라이 장치; 가변 래딕스(RADIX) 버터 플라이 장치로부터 수신받은 출력값에 대한 제1 래딕스(RADIX) 버터플라이 연산을 수행하는 제1 버터플라이 장치; 제1 버터플라이 장치로부터 수신 받은 출력값에 제1 곱셈 상수의 곱을 하는 제1 곱셈기; 및 제1 곱셈기로부터 수신 받은 출력값에 대한 제2 래딕스(RADIX) 버터플라이 연산을 수행하는 제2 버터플라이 장치를 포함한다. 이러한, 본 발명에 따르면 가변적인 값을 갖는 RADIX 버터플라이 연산을 통해 다양한 포인터에 대한 FFT 연산을 수행할 수 있는 효과를 기대할 수 있다. 또한, 다양한 포인터에 대한 FFT 연산을 수행하기 위한 비용 절감 및 처리 속도 개선 효과를 기대할 수 있다. 버터플라이, 고속 퓨리에 변환, FFT, RADIX, SDF, OFDM
Abstract:
PURPOSE: A method for control the size of a receiving signal and obtaining initial sync in a mobile wireless mesh network is provided to independently and simultaneously perform initial sync obtainment and automatic signal size control by using a PPA(Punctured Primary Advanced) preamble signal composed of one OFDM(Orthogonal Frequency Division Multiplexing) symbol section. CONSTITUTION: A receiving signal level is adjusted by comparing a first average value with a reference value. If the level adjustment value is not included in a stable range, a second average value is obtained by collecting the first sample number of samples from a mobile autocorrelation result value. The receiving signal level is adjusted by comparing the second average value with the reference value(S304). A third average value is obtained by collecting the second sample number of samples from the mobile autocorrelation result value. If the third average value exceeds an initial sync generation threshold value, initial sync is generated(S305). [Reference numerals] (AA) Start; (BB) End; (S301) Entering a mobile wireless mesh network; (S302) Executing mobile autocorrelation; (S303) More than a threshold value?; (S304) Adjusting the level of a receiving signal; (S305) Detecting initial synchronization
Abstract:
PURPOSE: A method for processing an initial ranging signal in a wireless telecommunication system and a method thereof are provided to both an initial ranging channel signal and a data channel signal by using equal sized FFT engines. CONSTITUTION: An apparatus for processing an initial ranging signal includes a ranging signal transmission processing unit(10) and a ranging signal reception processing unit(20). The ranging signal transmission processing unit comprises a ranging signal generating unit(11) generating a ranging signal, a FFT(Fast Fourier Transform) unit(12), and a signal interpolation unit(13). The signal generating unit generates an initial ranging code. The IFFT unit performs the IFFT(Inverse Fast Fourier Transform) calculation of the initial ranging code. The signal interpolation unit performs the signal interpolation of a signal outputted from the IFFT unit. The ranging signal reception processing unit comprises a demultiplexing unit(21), K sized FFTs(22,23), correlators(24,25), initial ranging code generating unit(26), K sized FFTs(27,28), and a peak detector(29).
Abstract:
PURPOSE: A method for compensating uplink initial ranging time error search range is provided to periodically change initial ranging search time location and to expand initial search range. CONSTITUTION: A base station receives a first ranging code from a terminal(S100). The base station generates a second ranging code(S110). The base station designates a first search starting point and a second search starting point. A time offset detector detects the time offset(S140). A time offset calculator calculates the time offset(S150). The calculated time offset value and the ranging code value are transmitted to a MAC layer(S160).