A J Gasiewski remote sensing course notes lecture14

44 Pages·01.126 MB·English

by  A J Gasiewski

ECEN 5254
Remote Sensing Signals and Systems
Professor Albin J. Gasiewski
Lecture #14 – March 1, 2012
ECOT 246
303-492-9688 (O)
[email protected]
Classes: ECCS 1B14 TR 9:30-10:45 AM
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ECEN 5254 Remote Sensing Signals & Systems Spring 2012 University of Colorado at Boulder
Last Lecture
• Gain, noise figure, Friis formula
• Y-factor
• Gain & offset fluctuations
• Homodyne detection
• Linear calibration
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ECEN 5254 Remote Sensing Signals & Systems Spring 2012 University of Colorado at Boulder
Today’s Lecture
• Linear N-port devices
• Bosma's theorem
• Mixers, SSB/DSB detection
• LO noise suppression
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ECEN 5254 Remote Sensing Signals & Systems Spring 2012 University of Colorado at Boulder
Typical Radiometer System - Detailed
Many components (both passive and active) between antenna
port and detectors – whether in a radiometer or radar!
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Linear N-Port Devices
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Complex Power Waves
Single-port
I(z)
linear network
+
Z
o
Z V(z) Z
~
o l
E
-
o
z
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Complex Power Waves*
Single-port
I(z)
linear network
+
Z
o
Z V(z) Z
~
o l
E
-
o
z
↔
*Kurokawa, IEEE Trans MTT, 1964
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Complex Power Waves - Maximum Power
I(z = 0)
At network terminals (z = 0):
+
V(z = 0) Z
l
-
Maximum available power from source
(exchangeable power)
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Interpretation of a Wave
I(z = 0)
+
Thevenin equivalent Z
o
circuit of source: V(z = 0) Z
~
l
E
-
o
Maximum available power from source,
(a = incident power wave)
10
V-I ↔ a-b Relationship
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