Minimum peak transmit power using SAR equation

## Syntax

``pt = radareqsarpow(r,lambda,snr,tau,rnggain,azgain)``
``pt = radareqsarpow(r,lambda,snr,tau,rnggain,azgain,Name,Value)``

## Description

example

````pt = radareqsarpow(r,lambda,snr,tau,rnggain,azgain)` returns the SAR peak transmit power.```

example

````pt = radareqsarpow(r,lambda,snr,tau,rnggain,azgain,Name,Value)` specifies additional options using name-value arguments.```

## Examples

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Estimate the peak transmit power for a side-looking SAR operating at a frequency of 5.3 GHz to form an image of a target at 50 km. Assume a radar cross-section (RCS) of 1 m${}^{2}$ and rectangular waveform with a bandwidth of 0.05 microseconds. The antenna gain is 30 dB and the minimum SNR required to make a detection 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); r = 50e3; tau = 0.05e-6; G = 30; SNR = 30; rnggain = 29.8; azgain = 42.7;```

Compute the peak transmit power.

`pt = radareqsarpow(r,lambda,SNR,tau,rnggain,azgain,'Gain',G)`
```pt = 17.4555 ```

## Input Arguments

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Range to target in meters, specified as a scalar, a column vector, a 1-by-2 row vector, or a 2-column matrix.

• Specify this argument as a scalar or a column vector for a monostatic radar.

• Specify this argument as a 1-by-2 row vector or as a 2-column matrix for a bistatic radar.

• The first element or column corresponds to the range from the transmitter to the target.

• The second element or column corresponds to the range from the target to the receiver.

Data Types: `double`

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`

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 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: `'Ts',293,'Gain',12`

Target radar cross-section in square meters, specified as a scalar or a vector. `radareqsarpow` 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, `radareqsarpow` 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`

Atmospheric absorption loss in decibels, specified as a scalar, a column vector, a 1-by-2 row vector, or a 2-column matrix.

• Specify this argument as a scalar or a column vector to represent the atmospheric absorption loss for a one-way path.

• Specify this argument as a 1-by-2 row vector or as a 2-column matrix to represent a transmit path and a receive path.

• The first element or column corresponds to the atmospheric absorption loss for the transmit path.

• The second element or column corresponds to the atmospheric absorption loss for the receive path.

Data Types: `double`

Propagation factor in decibels, specified as a scalar, a column vector, a 1-by-2 row vector, or a 2-column matrix.

• Specify this argument as a scalar or a column vector to represent the propagation factor loss for a one-way path.

• Specify this argument as a 1-by-2 row vector or as a 2-column matrix to represent a transmit path and a receive path.

• The first element or column corresponds to the propagation factor for the transmit path.

• The second element or column corresponds to the propagation factor for the receive path.

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`

## Output Arguments

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SAR peak transmit power in watts, returned as a vector.

## Version History

Introduced in R2021a