Figure 5 shows a RF amplifier. The datasheet provides the S-parameter at 390MHz is given as...

  

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Figure 5 shows a RF amplifier. The datasheet provides the S-parameter at 390MHz is given as below: Su=0.39 / 163° S21 = 5.1962° S12= 0.05/61° S22 0.36-38° ZG 50 2, generator output impedance. Zo=75 02, characteristic impedance of the 1/4 transmission line. Zant 150 2, antenna input impedance Vp phase velocity 58% of speed of light. C = 3x10^8 m/s is the speed of light. a. State the equation for the relationship between the load impedance Z₁ and input impedance Zin with respect to the characteristic impedance Zo for a 2/4 transmission line. Calculate the value of Zo of the 2/4 transmission line so as to achieve a 50 2 load impedance seen by the OMN. (5 marks) b. Determine the stability of the RF transistor design and state its stability. (5 marks) c. Calculate the load reflection coefficient for conjugate match. d. Calculate the source reflection coefficient for conjugate match. (5 marks) (5 marks) e. Given that the results obtained from a Smith Chart are as below, calculate the component values for the output matching networks (OMN) to simultaneously conjugate match the transistor for maximum gain. Draw the circuit of the OMN using a RF NPN transistor. Smith Chart info: Series C (load)=-j1.28 ohm Shunt L (output of transistor) = -j0.79 mhos (5 marks) VG ZG Input Matching Output Matching Q1 Network (IMN) Network (OMN) Zo Zant ZL 2/4 Figure 5: RF amplifier with transmission line matching network Figure 5 shows a RF amplifier. The datasheet provides the S-parameter at 390MHz is given as below: Su=0.39 / 163° S21 = 5.1962° S12= 0.05/61° S22 0.36-38° ZG 50 2, generator output impedance. Zo=75 02, characteristic impedance of the 1/4 transmission line. Zant 150 2, antenna input impedance Vp phase velocity 58% of speed of light. C = 3x10^8 m/s is the speed of light. a. State the equation for the relationship between the load impedance Z₁ and input impedance Zin with respect to the characteristic impedance Zo for a 2/4 transmission line. Calculate the value of Zo of the 2/4 transmission line so as to achieve a 50 2 load impedance seen by the OMN. (5 marks) b. Determine the stability of the RF transistor design and state its stability. (5 marks) c. Calculate the load reflection coefficient for conjugate match. d. Calculate the source reflection coefficient for conjugate match. (5 marks) (5 marks) e. Given that the results obtained from a Smith Chart are as below, calculate the component values for the output matching networks (OMN) to simultaneously conjugate match the transistor for maximum gain. Draw the circuit of the OMN using a RF NPN transistor. Smith Chart info: Series C (load)=-j1.28 ohm Shunt L (output of transistor) = -j0.79 mhos (5 marks) VG ZG Input Matching Output Matching Q1 Network (IMN) Network (OMN) Zo Zant ZL 2/4 Figure 5: RF amplifier with transmission line matching network