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  1. #1
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    Maximum vehicle speed.

    Please I want the solution for the question below:

    Consider a mobile wireless system, using QPSK modulation at 25 Ksymbols/s, and a carrier frequency of 1900 MHz. What is the fastest speed in km/h that is permissible for a vehicle using such system, if its required that the change in phase due to Doppler spread does not exceed 5 degree/ symbole?

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  2. #2
    Advanced Member level 1
    Points: 2,383, Level: 11

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    Re: Maximum vehicle speed.

    if this is a homework question, say so

    guidance:
    at your symbol rate, what is the time per symbol?

    how much time per symbol is a 5 degree shift?

    doppler shift:
    https://en.wikipedia.org/wiki/Doppler_effect
    the radar section

    remember that radar requires the return signal, while you do not



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