Question

You are on an interview with Sungsam LTE and the interviewer shows you their new 2300 MHz cell phone transceiver and antenna printed circuit board (PCB) shown below. "Between the RF source and antenna is a matching network of small circuit elements (i.e. inductor, capacitor or resistor) - the antenna feedline has a characteristic impedance Zo of 50 Ohms", she exclaims. She goes on to request you show her using her Smith Chart how you would 'match the PCB trance antenna to the RF source 1. tenna feed line PCB trace antenna F source RF IC) Matching network www.iot-bits.com She tells you the antenna (load) impedance was measured in the RF lone Lab using a vector network analyzer, to be 45+j10 Ω. Use the Smith Chart Rules (found in the tutorial presented in class) for series and parallel capacitors and inductors, design a component matching network that transforms the load impedance to a purely resistive impedance presented to the RF source of 50 Ohms. YOU MUST LABEL ALL resistive and/or conductive circles as well as reactive curves and associated reactance values, very carefully and precisely to receive full credit. You must then show the algebraic calculations that complement the Smith Chart and calculate the reactance values according to the formulas in the tutorial Once the C and or L values are calculated you can go to the parts drawer and pick out the correct C and L and solder it between the antenna and RF source. And then maximum power can be delivered to the antenna so that RFlone customers are happy using their cell phone. Staple your Smith Chart and calculations behind this page I, not at the back. Again if you do not provide a complete Smith Chart work impedance calculations on a separate page, points will be deducted. Put the Smith chart and calculations page right after this page. (30 pts)

Answer 1

Solution:

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