MATLAB Examples

# Figures 9 and 10. CNR per Column (element) as a function of azimuth angle.

## Contents

Coded by Ilias Konsoulas, 16 Sept. 2018. Code provided for educational purposes only. All rights reserved.

```clc; clear; close all; ```

## Radar System Operational Parameters

```radar_oper_params; ```

## Thermal Noise Power Computations

```thermal_noise_power; ```

## Clutter Patch Geometry Computations

```clutter_patch_rcs; ```

## Compute Array Transmit and Element Receive Power Gains

```Tx_Rx_power_gains; ```
```Warning: The value of local variables may have been changed to match the globals. Future versions of MATLAB will require that you declare a variable to be global before you use that variable. ```

## Plot in polar coordinates the magnitude of the element voltage gain

```figure('NumberTitle', 'off','Name', ... 'Figure 9. The element power pattern. A -30-dB backlobe level is assumed.'); polardb(phi*pi/180,10*log10(gel),-60,'g'); ``` ## Plot the Array Factor

```figure('NumberTitle', 'off','Name','The voltage Array Factor for N=18 elements.','Position',[1 1 1000 400]); subplot(1,2,1); polardb(phi*pi/180,10*log10(abs(AF)/max(abs(AF))),-60,'r') subplot(1,2,2); plot(phi, 10*log10(abs(AF))); grid on; ylim([-30 15]); xlim([-180 180]); tightfig; ``` ## Calculate and Plot the Clutter to Noise Ration (CNR) for each clutter patch

```ksi = Pt*Gtgain.*Grec*lambda^2*sigma/((4*pi)^3*Pn*10^(Ls/10)*Rcik^4); % Eq. (58) figure('NumberTitle', 'off','Name','Figure 10. Received CNR per column as a function of azimuth. ','Position',[1 1 650 500]); plot(phi, 10*log10(abs(ksi)),'LineWidth',1.5); grid on; ylim([-80 40]); xlim([-180 180]); ylabel('CNR (dB)'); xlabel('Azimuth Angle (deg)'); title('CNR as a function of Azimuth angle'); ``` ## Total CNR per element per pulse:

```format long 10*log10(sum(ksi)) Pn ```
```ans = 47.006707274093024 Pn = 2.954464452899317e-14 ```