# eclipsingloss

Loss due to pulse eclipsing

Since R2021a

## Syntax

``LECL = eclipsingloss(PD,PFA,N)``
``LECL = eclipsingloss(PD,PFA,N,DU)``
``LECL = eclipsingloss(PD,PFA,N,DU, SW)``

## Description

example

````LECL = eclipsingloss(PD,PFA,N)` computes the statistical eclipsing loss, `LECL`, in decibels for an unmodulated rectangular pulse with a duty cycle of `0.1` given the probability of detection, `PD`, the probability of false alarm, `PFA`, and the number of received pulses, `N`. The function assuming you are using a square-law detector and a nonfluctuating target.```
````LECL = eclipsingloss(PD,PFA,N,DU)` computes the statistical eclipsing loss for an unmodulated rectangular pulse given the duty cycle, `DU`, of the transmitted waveform as an additional input argument.```
````LECL = eclipsingloss(PD,PFA,N,DU, SW)` computes the statistical eclipsing loss for radar echoes received from a chi-squared distributed target given the Swerling case number, `SW`, as an additional input argument. ```

## Examples

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Compute the statistical eclipsing loss for a single unmodulated rectangular pulse. Specify the probability of detection from `0.1–0.99` and probability of false alarm of `1e-6`.

```PD = 0.1:0.01:0.99; PFA = 1e-6; N = 1; LECL = eclipsingloss(PD,PFA,N);```

Plot the eclipsing loss.

```plot(PD,LECL) ylim([0 20]); xlabel('Probability of Detection'); ylabel('Eclipsing loss (dB)'); title('Statistical Eclipsing Loss vs P_d for Swerling 0 Target'); grid on;```

## Input Arguments

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Probability of detection, specified as a positive scalar in the range of `[0.1, 0.999999]` or as a length-J vector with each element in the range `[0.1, 0.999999]` .

Probability of false alarm, specified as a positive scalar or as a length-K vector with each element in the range ```[1e-15, 1e-3]```.

Number of received pulses, specified as a positive scalar.

Duty cycle, specified as a scalar or length-`M` vector.

• If you set `DU` as a scalar, the function computes the eclipsing loss for an unmodulated rectangular pulse with duty cycle in the range `(0, 1)`.

• If you set `DU` as a length-M vector, the function computes the eclipsing loss for an arbitrary waveform specified using the time domain samples taken over a one pulse repetition interval.

Swerling case number, specified as one of these

• `'Swerling0'`

• `'Swerling1'`

• `'Swerling2'`

• `'Swerling3'`

• `'Swerling4'`

• `'Swerling5'`

## Output Arguments

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Eclipsing loss, returned as a J-by-K matrix in decibels with rows corresponding to `PD` and columns corresponding to `PFA`.

## Version History

Introduced in R2021a