Lec 5 Network Analysis.pdf - ECE 113 Lecture 5 Network Analysis References Pozar Chapter 4 1s1617 Revision October 2016 We are familiar with\u2026 Circuits

Lec 5 Network Analysis.pdf - ECE 113 Lecture 5 Network...

This preview shows page 1 - 12 out of 50 pages.

ECE 113 1s1617 Revision October 2016 Lecture 5: Network Analysis References: Pozar, Chapter 4
Image of page 1
Circuits at LOW frequencies Circuit dimensions are small relative to wavelength (λ = c/f) o e.g. @ f = 100 kHz , λ ≈ 3 km Treat as interconnection of lumped passive/active elements Voltages and Currents defined at any point in the circuit o Use KCL, KVL, and Ohm’s Law to analyze these circuits We are familiar with…
Image of page 2
Measurement of total voltage and/or cu rrent is difficult (or almost imposs ible) Circuit dimension is comparable to wavelength o e.g. @ f = 1 GHz , λ ≈ 30 cm Measurements require clearly defined terminal pairs Complete circuit analysis requires solving Maxwell’s Equations For RF/Microwave Circuits…
Image of page 3
It is more convenient to express our circuits (networ ks) in terms of traveling waves (incident and reflected waves ) Recall from introduction to reflection coefficient (last lectures of EEE 53) that total voltage at high frequencies can be expressed as the sum of incident and reflected waves OUR GOAL: Convert representation in terms of traveling waves to conventional low frequency models At high frequencies…
Image of page 4
Once traveling wave voltages and currents have been defined at various points in an RF/Microwave network, we a re able to relate these terminal or “port” quantities to each other This results in a matrix description of our N-port network Useful when we discuss high-frequency representations of our active networks N-Port Network Parameters
Image of page 5
N-Port Network 𝑉𝑉 2 = 𝑉𝑉 2 + + 𝑉𝑉 2 𝑉𝑉 1 = 𝑉𝑉 1 + + 𝑉𝑉 1 𝑉𝑉 3 = 𝑉𝑉 3 + + 𝑉𝑉 3 𝑉𝑉 4 = 𝑉𝑉 4 + + 𝑉𝑉 4 𝑉𝑉 𝑁𝑁 = 𝑉𝑉 𝑁𝑁 + + 𝑉𝑉 𝑁𝑁
Image of page 6