Changes

Place and connect all the parts as shown in the above figure. The circuit of this part is similar to the circuit of the previous part, except for the fact that you need to introduce a Doppler frequency shift in the echo signal. To model this additionally frequency-shifted echo signal, you introduce a second FM modulator X2 which is fed by the same triangular waveform V1 but with a slightly shifted carrier frequency of 1.0001GHz. For the purpose of this tutorial and to demonstrate a practical simulation, we assume that the Doppler frequency shift is f_d = 100kHz. This translates to a target velocity of v_r = f_dλ₀/2 = 15km/s, which is extremely high. But remember that typical vehicular speeds would only produce a Doppler shift of few hundreds of Hertz at 1GHz. The VCVS source E1 creates an exact replica of V1 at the input of FM modulator X2 that is amplified by the '''Gain Block''' A1, which is a copy of the gain block '''PA''' placed before the transmit antenna load '''Rant'''. The output of A1 then passes through a '''Radar Echo Block''' of the same [[parameters]] as the previous part and with a target range of 1500m. In this way, the signal at Node 9 at the output of the radar echo block gives a good representation of the echo signal received at the aperture of the receive antenna.

Run a Transient Test of your modulator circuit with the following [[parameters]]:

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