frequency-shift造句
例句与造句
- Research on frequency - shift sending equipment with microcomputer
移频发送设备的电子化方案研究 - Afsk for audio frequency - shift keying
音频频移键控 - Study on the model of transmitting cable crosstalk in frequency - shift track circuit
移频轨道电路传输电缆串音模型的研究 - Fsk for frequency - shift keying
频移键控 - The practice of doppler frequency - shift signal extraction in ultrasonic blood flow detector
多普勒频移信号提取技术在超声血流检测中应用 - It's difficult to find frequency-shift in a sentence. 用frequency-shift造句挺难的
- The optical sampling with frequency - shift , asynchronous optical sampling , and photonic analog to digital conversion based on time - interleave were investigated , included the theoretical analysis and experimental demonstration
建立了频差法光脉冲取样、异步光取样及基于时分光取样的光子模数转换实验装置。 - Because frequency - shift signal is a kind of modulation signal , it ' s waveform is two ac sine signal of alternating i . e . upper frequency and lower frequency which was generated by low frequency modulating middle frequency
由于移频信号是一种调频信号，其波形为低频信号调制中心载频信号后产生的低端载频（下边频）和高端载频（上边频）两个交替变化的正弦交流信号。 - The ministry of railway has developed two kinds of frequency - shift track circuits based on the primary 4 - information frequency - shift system : 18 - information frequency - shift auto - blocking track circuit made in china and um - 71 jointless track circuit made in france , and put them into use on some important lines . but at the mean while , the safety of running train becomes austerer and austerer
铁道部根据我国国情,在原有4信息移频制式的基础上,研制开发了两种移频轨道电路:国产18信息移频自动闭塞系统和法国um - 71无绝缘轨道电路系统,并将其应用到我国部分主要线路上。 - At the last we program the parameter detecting methods for frequency - shift track signal with c language and assembly language base on code composer studio of dsp . then we realize it on the dsp chip of tms320f2812 . experiments shows that it can satisfy the demand of real time and precision
最后在dsp的集成开发环境ccs ( codecomposerstudio )上采用c语言和汇编语言混合编写移频轨道信号的参数检测算法,并将该算法移植到dsp芯片( tms320f2812 )上实现,测试结果表明上述算法能够满足实时性和精度的要求。 - The actively and passive mode - locked fiber ring laser and two types of photonic switching , slalom ( semiconductor laser amplifier loop mirror ) and uni ( ultrafast nonlinear interferometer ) were developed . this thesis presented the principle and the requirements for the optical of frequency - shift sampling module under common conditions
研制了作为光取样脉冲源的主动锁模和被动锁模光纤激光器；半导体光放大器环镜及超高速非线性干涉仪的光子开关，并进行了频差法光取样、异步光取样及基于时分光取样的光子模数转换的实验研究。 - On the basis of the former research works , we present the detecting method as follows : for the narrow band characteristic of the track signal we use under - sampling instead of nyquist sampling to reduce the sampling rate . as to the carrier frequency , the spectrum of the 18 - information frequency - shift track signal has two peaks , then the carrier frequency is the average of the two peak frequency , to um - 71 jointless track signal , it has only one peak , then the carrier frequency is the peak frequency
针对移频轨道信号的窄带特性提出了使用欠采样技术代替奈奎斯特采样的方法,以降低信号的采样频率;国产18信息移频轨道信号频谱具有双峰,双峰频率平均值就是信号的载频频率,而um - 71无绝缘轨道信号频谱单峰,峰值频率即为信号的载频频率。 - In this paper , bit - error rate performance analyses are presented for coded and un - coded frequency hopping m - ary frequency - shift keyed systems under the condition of additive white gaussian noise ( awgn ) and partial band noise jamming and multitone jamming . the use of error - correct codes provide a way to improve the performance of frequency hopping system , particularly the use of reed - solomon code in a fh system under the condition of partial band noise jamming can greatly improve the performance of system . so we provide the way of coding and decoding of rs code in c language . in the end , we offer the simulation of the performance of time diversity fh / 2fsk system over partial band jamming noise channels
第一章为绪论，叙述跳频通信的发展趋势，以及基本概念，第二章及第三章介绍提高抗部分频带干扰的前向纠错码reed - solomon码的原理和实现方法。第四章研究跳频通信系统在各种干扰条件下的性能。最后在第五章以fh mfsk系统为例，探讨在部分频带干扰下的系统性能，并进行计算机仿真，仿真结果表明采用分集技术和各种编码技术对于系统的性能改善具有明显的效果。