# ps 6 soln - #6 1 Problem 1a On the left is the plot of...

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1) # 6 Problem 1aOn the left is the plot of Stability Factor(K) and Stability Measure (B) against frequency. B > 0 for all the frequencies of interest. But, we see that K < 1 for frequencies less than 96 GHz. This suggests that the circuit is potentially unstable below 96 GHz and unconditionally stable above 96 GHz. At 50 GHz, the circuit is potentially stable as K<1. So MAG is not defined at 50 GHz. We only have MSG (Maximum stable gain) defined. MSG = 15.031 dB. When the device is unconditionally stable, MSG=MAG. This value agrees well with the calculated value of 15.10 dB.
Problem 1b Shown on the left are the Load and Source stability circles of the device at 50 GHz. It is clear that the device is potentially unstable at this frequency. We'll add (tune) series or shunt stabilization at the input/output to make the circuit unconditionally stable at this frequency. Series Stabilizing at Input Observe that a series resistor of 5 Ohm, stabilizes the network at 50 GHz pushing the source and load
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