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radareqrng

Maximum theoretical range estimate

Since R2021a

Description

maxrng = radareqrng(lambda,SNR,Pt,tau) estimates the theoretical maximum detectable range maxrng for a radar operating with a wavelength of lambda meters with a pulse duration of Tau seconds. The signal-to-noise ratio is SNR decibels, and the peak transmit power is Pt watts.

example

maxrng = radareqrng(lambda,SNR,Pt,tau,Name,Value) estimates the theoretical maximum detectable range with additional options specified by one or more Name,Value pair arguments.

example

Examples

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Estimate the theoretical maximum detectable range for a monostatic radar operating at 10 GHz using a pulse duration of 10 μs. Assume the output SNR of the receiver is 6 dB.

lambda = physconst('LightSpeed')/10e9;
SNR = 6;
tau = 10e-6;
Pt = 1e6;
maxrng = radareqrng(lambda,SNR,Pt,tau)
maxrng = 
4.1057e+04

Estimate the theoretical maximum detectable range for a monostatic radar operating at 10 GHz using a pulse duration of 10 μs. The target RCS is 0.1 m². Assume the output SNR of the receiver is 6 dB. The transmitter-receiver gain is 40 dB. Assume a loss factor of 3 dB.

lambda = physconst('LightSpeed')/10e9;
SNR = 6;
tau = 10e-6;
Pt = 1e6;
RCS = 0.1;
Gain = 40;
Loss = 3;
maxrng2 = radareqrng(lambda,SNR,Pt,tau,'Gain',Gain, ...
    'RCS',RCS,'Loss',Loss)
maxrng2 = 
1.9426e+05

Input Arguments

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Wavelength of radar operating frequency, specified as a positive scalar. The wavelength is the ratio of the wave propagation speed to frequency. Units are in meters. For electromagnetic waves, the speed of propagation is the speed of light. Denoting the speed of light by c and the frequency (in hertz) of the wave by f, the equation for wavelength is:

λ=cf

Data Types: double

Input signal-to-noise ratio (SNR) at the receiver, specified as a scalar or length-J real-valued vector. J is the number of targets. Units are in dB.

Data Types: double

Transmitter peak power, specified as a positive scalar. Units are in watts.

Data Types: double

Single pulse duration, specified as a positive scalar. Units are in seconds.

Data Types: double

Name-Value Arguments

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Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: SNR,10

Radar cross section specified as a positive scalar or length-J vector of positive values. J is the number of targets. The target RCS is nonfluctuating (Swerling case 0). Units are in square meters.

Data Types: double

System noise temperature, specified as a positive scalar. The system noise temperature is the product of the system temperature and the noise figure. Units are in Kelvin.

Data Types: double

Transmitter and receiver gains, specified as a scalar or real-valued 1-by-2 row vector. When the transmitter and receiver are co-located (monostatic radar), Gain is a real-valued scalar. Then, the transmit and receive gains are equal. When the transmitter and receiver are not co-located (bistatic radar), Gain is a 1-by-2 row vector with real-valued elements. If Gain is a two-element row vector it has the form [TxGain RxGain] representing the transmit antenna and receive antenna gains. Units are in dB.

Example: [15,10]

Data Types: double

System losses, specified as a scalar. Units are in dB.

Example: 1

Data Types: double

Custom loss factors specified as a scalar or length-J column vector of real values. J is the number of targets. These factors contribute to the reduction of the received signal energy and can include range-dependent Sensitive Time Control (STC), eclipsing, and beam-dwell factors. Units are in dB.

Example: [10,20]

Data Types: double

Units of the estimated maximum theoretical range, specified as one of:

  • 'm' meters

  • 'km' kilometers

  • 'mi' miles

  • 'nmi' nautical miles (U.S.)

Output Arguments

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The estimated theoretical maximum detectable range, returned as a positive scalar. The units of maxrng are specified by unitstr. For bistatic radars, maxrng is the geometric mean of the range from the transmitter to the target and the receiver to the target.

More About

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References

[1] Richards, M. A. Fundamentals of Radar Signal Processing. New York: McGraw-Hill, 2005.

[2] Skolnik, M. Introduction to Radar Systems. New York: McGraw-Hill, 1980.

[3] Willis, N. J. Bistatic Radar. Raleigh, NC: SciTech Publishing, 2005.

Extended Capabilities

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Version History

Introduced in R2021a