124
5 Performance Characteristics of Radar Location …
where K sup0 —suppression coefficient of radar system without additional techniques
(units, algorithms) of noise protection; K sup —radar suppression coefficient with
additional anti-jamming measures.
To estimate the effectiveness of spatial-time signals processing operations, another
energy criterion of interference immunity is used sometimes—energy efficiency
coefficient.
K en =
q
q 0
,
(5.97)
where q—signal-to-/(noise + internal noise) ratio in power at output of processing
system; q 0 —the same ratio, but with no noise.
In some cases, the effectiveness of interference eliminators is evaluated by
interference immunity coefficient, which is determined by the following expression:
K nn =
P n3
P n
P no = const
,
(5.98)
where P np —minimal noise power at input of the same radar system with interference protecting (algorithm) unit; P n —minimal noise power at input of the same
system without interference protecting (algorithm) unit, at which a specified degree
of system suppression is achieved; P cd —probability of correct detection of a target.
Advantage of this interference immunity criterion concludes in that by its using it
is possible to characterize the effectiveness of different interference protection units
and algorithms. Disadvantage concludes in impossibility of estimation of the system
as a whole since it does not consider such characteristics of radar system as radiating
power, antenna gain factor, etc., at the most determining the system interference
immunity.
More complete criterion, permitting to consider both effectiveness of interference
protection units and algorithms and technical parameters of the system, effecting on
its interference immunity, is an overall coefficient (index) K ov , calculated in decibels:
K ov = K key + K add ,
(5.99)
where K key and K add —key and additional criteria interference immunity.
Key indicator K key is determined by transmitter power, resolution capability in
angular coordinates, in range and approaching (rendezvous) velocity and can be
introduced, for example, as follows:
K key = 10 lg(P rad τ τ f s G a ),
(5.100)
where P rad —radiation power; f s —signal bandwidth; τ —target observing time;
G a —absolute gain of antenna. Values P rad , τ and f s in expression (5.100) are
dimensionless due to its normalizing to 1 W, 1 s and 1 Hz, correspondingly.
5 Performance Characteristics of Radar Location …
where K sup0 —suppression coefficient of radar system without additional techniques
(units, algorithms) of noise protection; K sup —radar suppression coefficient with
additional anti-jamming measures.
To estimate the effectiveness of spatial-time signals processing operations, another
energy criterion of interference immunity is used sometimes—energy efficiency
coefficient.
K en =
q
q 0
,
(5.97)
where q—signal-to-/(noise + internal noise) ratio in power at output of processing
system; q 0 —the same ratio, but with no noise.
In some cases, the effectiveness of interference eliminators is evaluated by
interference immunity coefficient, which is determined by the following expression:
K nn =
P n3
P n
P no = const
,
(5.98)
where P np —minimal noise power at input of the same radar system with interference protecting (algorithm) unit; P n —minimal noise power at input of the same
system without interference protecting (algorithm) unit, at which a specified degree
of system suppression is achieved; P cd —probability of correct detection of a target.
Advantage of this interference immunity criterion concludes in that by its using it
is possible to characterize the effectiveness of different interference protection units
and algorithms. Disadvantage concludes in impossibility of estimation of the system
as a whole since it does not consider such characteristics of radar system as radiating
power, antenna gain factor, etc., at the most determining the system interference
immunity.
More complete criterion, permitting to consider both effectiveness of interference
protection units and algorithms and technical parameters of the system, effecting on
its interference immunity, is an overall coefficient (index) K ov , calculated in decibels:
K ov = K key + K add ,
(5.99)
where K key and K add —key and additional criteria interference immunity.
Key indicator K key is determined by transmitter power, resolution capability in
angular coordinates, in range and approaching (rendezvous) velocity and can be
introduced, for example, as follows:
K key = 10 lg(P rad τ τ f s G a ),
(5.100)
where P rad —radiation power; f s —signal bandwidth; τ —target observing time;
G a —absolute gain of antenna. Values P rad , τ and f s in expression (5.100) are
dimensionless due to its normalizing to 1 W, 1 s and 1 Hz, correspondingly.