Phase 2 Flashcards
What polarization has a rotating e-field
Non-linear
The effective change in frequency of a received signal due to the relative velocity of the transmitter with respect to the receiver describes what propagation effect?
Doppler shift
What is the dominant propagation effect and frequency range of a surface wave?
Diffraction and 300 kHz to 30 MHz
What term refers to a band of frequencies used for a particular purpose?
channel
Which of the following is not an advantage of digital communications over analogue?
Received signal is replica of the transmitted signal
Any unwanted signal accepted or generated by a receiver, which corrupts the wanted signal at the receiver output is the definition of which term?
Noise
Difference between the highest and lowest frequencies of a signal is the definition of which of the following terms?
Bandwidth
Which communications obstacle may be minimized by increasing the strength of the information signal or by using highly directional antennas.
Attenuation
The amount of time that the transmitter is on during each cycle is the definition of which term?
Pulse Repetition Frequency (PRF)
The time from the end of recovery time to the beginning of the next pulse is the definition of which term?
Available listening time
Which scan sweeps through a sector and transmits while scanning in one direction only?
Uni-direction
Which parameter affects the minimum range that a target may be detected?
▪ Pulse Width (PW)
Which scan involves the use of one beam that cycles between the two or four narrow lobes?
Sequential Lobing
The greatest range from which target returns are expected to arrive, before the next pulse is transmitted is the definition of which term?
Maximum ambiguous range
The concept of moving electrons to an excited energy level through the input of appropriate energy, and then encouraging them to decay simultaneously, generating a coherent beam of propagating photons is the definition of which term?
Stimulated emission
