In the OSNR model for EDFA amplifiers, SNR OUT = 1/(1/SNR IN + FhvB/P IN ), what does SNR IN represent?（）
第1题：
A. the signal to noise of the current optical amplifier
B. the signal to noise of the previous amplifier or source
C. the signal to noise introduced by the optical multiplexer
D. the accumulated noise to signal ratio of the optical channel
第2题：
A. lower cost
B. higher chirp
C. easier to manufacture
D. higher dispersion tolerance
E. higher optical signal-to-noise ratio
第3题：
The maximum data rate of any single wireless link can be described by the shannon’s theorem which is related to the（）in hertz，and the（）on the channel
A．signal frequency B．bandwidth C．carrier frequency D．noise frequency A．signal B．caeeier C．noise D．data signal
第4题：
What are three factors that limit the maximum distance of an amplified optical signal without regeneration? （）(Choose three.)
第5题：
A.The received power on the resource elements that carry cell-specific reference signals
B.wideband power
C.N times the Reference Signal Received Power divided by the total received power in the channel bandwidth
D.Signal to Interference plus Noise Ratio
第6题：
A. fiber dispersion
B. signal attenuation
C. transmitter power
D. amplifier bandwidth
E. receiver dispersion tolerance
第7题：
A. signal strength 5dBm
B. signal strength 6dBm
C. noise level 4dBm
D. noise level 5dBm
第8题：
信噪比(signal to noise ratio,SNR)是MRI最基本的质量参数，其正确的概念表述应为：()。
A、图像的亮度与暗度之比
B、两个像素的信号强度之比
C、两个体素的信号强度之比
D、图像的信号强度与背景强度之比
E、图像的T1值与背景噪声T1值之比
第9题：
Which of these terms refers to call issues that cause variations in timing or time of arrival？（）
第10题：
信噪比（signal to noise ratio,SNR）是MRI最基本的质量参数，其正确的概念表述应为（）