代做EEME30004 Communications and Networks RF systems Homework #3代做留学生SQL语言程序

EEME30004 Communications and Networks

RF systems Homework #3

Q1: The Triquint T1G6000528 GaN HEMT has the following S-parameters at 1.9 GHz:

S11 = 0.869∠ − 159°

S12 = 0.031∠ − 9°

S21 = 4.250∠61°

S22 = 0.507∠ − 117°

Determine the stability of this transistor by using the K — Δ test and the μ-test.

Q2 A SiGe HBT device has the following S-parameters at 2 GHz: S11 = 0.88∠ − 115°, S12 =

0.029∠31° , S21 = 9.4∠110° , and S22 = 0.328∠ − 67° .  Determine  the   stability  of  this transistor.

Q3 We have a receiver with 5 components below.

Figure Q3

(a) Calculate the total gain in dB.

(b) Calculate the total IIP3 in dBm.

(c) What is the overall noise figure (NF or F) in dB?

(d) What is the overall noise temperature in Kelvin?

(e) Assume all components except the IF amplifier remain unchanged. If you want the total receiver noise figure to be reduced to  1.5 dB, can this be achieved by improving only the IF amplifier’s noise figure? If it is achievable, determine the required noise figure of the IF amplifier.

Q4 A receiver front-end circuit is shown below. The operating frequency is 1805 – 1880 MHz, and the physical temperature of the system is 300 K. A noise source with Ni  = —95 dBm is applied to the receiver input.

Figure Q4

(a) What is the equivalent noise temperature of the source over the operating bandwidth?

(b) What is the noise figure (in dB) of the amplifier?

(c) What is the noise figure (in dB) of the cascaded transmission line and amplifier?

(d) What is the total noise power output (in dBm) of the receiver over the operating bandwidth?