[試題] 98上盧信嘉微波系統導論期中考

看板NTU-Exam作者CCSam (GMT)時間15年前 (2009/12/06 00:25)推噓6(6推 0噓 1→)

留言7則, 7人參與討論串1/1

課程名稱︰微波系統導論課程性質︰選修課程教師︰盧信嘉開課學院：電資學院開課系所︰電機工程學系考試日期（年月日）︰2008/11/17 考試時限（分鐘）：3小時是否需發放獎勵金：（如未明確表示，則不予發放）是 note: Open book 試題 : Introduction to Microwave Systems Midterm examination 1. (10pts) Please plot the following two traces from 1GHz to 3GHz on Smith chart. Please indicate the frequencies at both ends of the traces and Zo = 50 Ohm a. Zin trace for a 40 Ohm resistor in series with a 4nH inductor. b. Yin trace for a 100 Ohm resistor in parallel with a 0.6pF capacitor 2. (10pts) Fig 2.13 shows a matched 3dB attenuator. Find resistor values for a matched 10dB attenuator. 3. (30pts) The measured two-tone test of a receiver is given at Fig. P3. a. Find its output IP3, gain and P1dB. b. The noise figure of the receiver is 6dB. If the receiver is fed with an antenna with noise temperature Ta = 100K, and the desired output SNR is 15dB, find the linear and spurious free dynamic range. Assume the receiver bandwidth is 200MHz. c. If ASK and basic threshold detection is used, what is the BER? 4. (15pts) The signal received by a GPS receiver is about only -130dBm using a 0dB gain antenna at earth surface at L1 band. a. Can you use a hign-gain antenna to increase the received signal level? Please give your reason to support your answer. b. What is the required EIRP at satellite? The satellite orbit is 20,200km above earth. Assume only free space propagation. 5. (10%) A reflector antenna used for a cellular base-station backhaul point-to-point radio link operating at 38GHz, with gain of 32dB. If the radiation efficiency is 60%, find the beamwidth of the antenna if the main beam is assumed to have equal beamwidths in both planes. 6. (15pts) We will design a 3rd order Butterworth low pass filter with cutoff frequency at 3.0GHz. There are two possible implementations: started from capacitor or inductor. Please calculate all component values for both cases. Larger inductance usually takes more substrate area. Please comment on both cases based on this criterion. 7. (10pts) The textbook uses W <- -Wc/W to transform low-pass filters into highpass filters. Is it necessary to have the minus sign in the transformation? Please give the explanation to support your answer. -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 220.136.82.39

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CCSam

12/06 00:29, , 1^F

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vanillaXleft

12/06 04:16, , 2^F

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hectory

12/06 16:15, , 3^F

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