2 Electronic Support Flashcards
ESM receivers are used for _____ reaction.
Real-time
ES Receivers may be devided into two categories:
Threat Warning Receiver (TWR) and;
Reconaissance/Surveillance Receivers
What is a Threat Warning Receiver (TWR)?
Provides threat warning over a preset frequency range in real time. It gives you advanced warning that a threat is present.
TWR is _____ sensitivity.
Low
What is a Reconnaissance/Surveillance Receiver?
Have higher sensitivity and direction finding accuracy to measure more radar parameters. Can be real time or long analysis.
Reconnaissance/Surveillance Receivers are _______ sensitivty.
High
What are the four functions of an Electronic Support system?
Reception - radar pusle is intercepted and detected
Measurement - signal parameters are measured
Recognition - compare against library
Display / Report - to operator and CCS
What are three domains which ES systems must operate?
Signal Domain
Temporal Domain
Spatial Domain
Signal Domain
Receiver polarization and frequency must match
Temporal Domain
Receiver must be operating at the same time as the radar system transmits energy.
Spatial Domain
Antennas must be able to receive energy from the direction of the transmission
What are the performance requirements of ES systems?
Frequency coverage
Sensitivity and selectivity
Dynamic range
Bearing and elevation coverage
Quick Analysis Time
For a receiver to intercept a signal it must _____ and then ______
Cover the frequency band
Be tuned to the correct frequency of the transmitter
Sensitivity refers to the ability to ______
detect signals in noise (SNR)
A wide bandwidth _____ sensitivity.
Reduces
What is selectivity?
The ability to select a certain range of frequencies and reject all others.
Selectivity is _______ proportional to bandwidth.
A selective receiver is ______ sensitive.
Inversely
More
Remember sensitivity is inversely proportional to bandwidth.
If a receiver is very selective, it has ________ probablity of intercept.
Reduced.
Selectivity is the ability to select a certain range of frequencies and reject all others. It will not be able to cover a wide range all at once but it can cover one narrow range very well.