signal n. 1.信号,暗号;信号器。 2.动机,导火线 (for)。 3.预兆,征象。 call signal 【无线电】呼号。 an alarm signal 警报(器)。 an information signal 〔美国〕暴风警报(旗)。 an international code of signals 国际通用信号。 a signal of distress =a distress signal 船只失事信号。 adj. 1.暗号的,作信号用的。 2.显著的,非常的,优越的。 a signal victory [defeat] 大胜[败]。 vt.,vi. (〔英国〕 -ll-) 发信号[警报]给(人、船等);用信号[警报]通知(暴风、危险等);用动作[手势]示意;预示。 a signaling bomb 信号弹。
A functional unit that modulates and demodulates signals . one of the functions of a modem is to enable digital data to be transmitted over analog transmission facilities 一种对信号进行调制与解调的功能部件,调制解调器的功能之一就是使数字数据经由模拟传输设施进行传送。
J . mitola proposed software radio ( or software defined radio , sdr ) technology to deal with those problems , i . e . , digitizing waveforms as near as possible to rf , and modulating / demodulating signals by software 针对这些问题, j . mitola提出了的射频信号数字化、软件化处理的思想,即软件无线电技术,成为解决上述问题的有效途径。
The method is given to solve the problem in adaptive demodulation that adjudgement will worsen when the snr is low . by using the error signals to reduce the demodulated signals , the bit error rate will be improved 仿真中,针对dpsk信号的自适应解调中小信噪比下门限失效的问题,提出了利用误差改进门限判决的方法,将误码性能提高了1 2db 。
The test results show that different patterns of pd correspond to different demodulating signal waveforms , the pd phase angle in ac , and spectrum characteristics . therefore the pd patterns can be recognized by the uhf characters of different pd signals in gis 试验结果表明,不同缺陷类型的局部放电在其检波信号波形、局部放电工频相位分布和超高频频谱特征是有所不同的,可以依据这些特征对gis内的局部放电类型进行识别。
A gis pd measuring system is established , including a conventional pd measurement system , uhf detecting system and a pd spectrum system . we can obtain pd signal characters by this system , such as uhf transient signal waveforms , uhf demodulating signal waveforms , the pd phase angle in ac , pd spectrum , and discharge quantities 建立了gis局部放电测量系统,其中包括:常规局部放电测量系统、超高频检波测量系统和放电频谱测量系统等,通过测量系统得到了gis内局部放电的超高频暂态信号波形、检波信号波形、工频相位分布、频谱特征以及常规视在放电量等特征。