Maximum detectable range using SAR equation

Description

example

rng = radareqsarrng(lambda,snr,pt,tau,rnggain,azgain) returns the maximum detectable range for a SAR.

example

Examples

collapse all

Estimate the range for a side-looking SAR imaging a target with a radar cross-section (RCS) of 1 m${}^{2}$. The radar operates at a frequency of 5.3 GHz and has a peak power of 5 kW. The SAR uses a rectangular waveform with a pulse width of 0.05 microseconds. The antenna gain is 30 dB and the minimum detectable SNR is 30 dB. The range processing gain is 29.8 dB and the azimuth processing gain is 42.7 dB. Assume zero losses.

lambda = freq2wavelen(5.3e9);
pt = 5e3;

tau = 0.05e-6;

gain = 30;
SNR = 30;

rnggain = 29.8;
azgain = 42.7;

Compute the maximum detectable range. Express the result in kilometers.

rng = 205.6978

Input Arguments

collapse all

Wavelength of radar operating frequency in meters, specified as a positive real scalar.

Data Types: double

Required signal-to-noise ratio (SNR) in decibels, specified as a real scalar or a vector.

Data Types: double

Transmitter peak signal power in watts, specified as a positive real scalar or a vector.

Data Types: double

Pulse width at the antenna port in seconds, specified as a positive real scalar.

Data Types: double

SNR gain due to range processing in decibels, specified as a real scalar.

Data Types: double

SNR gain due to azimuth processing in decibels, specified as a real scalar.

Data Types: double

Name-Value Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Example: 'Ts',293,'Gain',12

Target radar cross-section in square meters, specified as a scalar or a vector. radareqsarrng assumes a nonfluctuating target (Swerling case 0).

Data Types: double

System noise temperature in kelvins, specified as a positive scalar.

Data Types: double

Antenna gain in decibels, specified as a scalar or 1-by-2 row vector.

• If you specify this argument as a two-element vector, the first element represents antenna transmit gain and the second element represents the antenna receive gain.

• If you specify this argument as a scalar, radareqsarrng assumes the antenna has equal transmit and receive gains.

Data Types: double

System loss in decibels, specified as a scalar or a vector.

Data Types: double

Custom factor in decibels, specified as a scalar or a vector. This argument contributes to the received signal energy and can include other factors.

Data Types: double

Unit of range length, specified as 'm' (meter), 'km' (kilometer), 'mi' (statute mile), or 'nmi' (nautical mile).

Data Types: char | string

Output Arguments

collapse all

Maximum detectable range, returned as a column vector expressed in the units specified using UnitStr. For bistatic radars, each element of rng is the geometric mean of the range from the transmitter to the target and the range from the target to the receiver.

Extended Capabilities

C/C++ Code GenerationGenerate C and C++ code using MATLAB® Coder™. 