clear all;close all;nhFig = 0; % Figure Number;SeaRegLx = 40e+3; % Sea region
length, unit: mSeaRegLy = 40e+3; % Sea region length, unit: m% 根据频域采样定理,在
确定采样周期即波束的足迹宽度之后,% 可以利用时域采样的采样点数目(通过空间频谱的宽度即根据时域采
样定理计算出采样点数),实现频域采样.% 对于海洋波谱而言,波谱宽度是非常宽的,因此其波谱宽度一般是
指包括了大部分能量(或者说主要的能量部分)的不完全谱宽度% 所以这里事先根据波谱函数计算主要能量部分
对应的谱宽度xSampleStep = 50; % unit: mySampleStep = 50;xNs = round( SeaRegLx /
xSampleStep );yNs = round( SeaRegLy / ySampleStep );x = linspace( -SeaRegLx / 2,
SeaRegLx / 2, xNs );y = linspace( -SeaRegLy/ 2, SeaRegLy / 2, yNs );% 海浪谱仿真g
= 9.8; % gravity acceleration% swell wave spectrum parameterSwellWaveLength =
1000; % 涌浪波长KswellWavePeak = 2 * pi / SwellWaveLength;SwellAngled=0;SwellAngle
= SwellAngled/ 180 * pi; % 涌浪与观测向夹角KxswellWavePeak = KswellWavePeak * cos(
SwellAngle );KyswellWavePeak = KswellWavePeak * sin( SwellAngle );SigmaKx = 2.5e-
3; % 涌浪谱宽度SigmaKy = 2.5e-3;SigmaHSwell = 2; %涌浪波高% wind wave spectrum
parameterWindAngle = 45 / 180 * pi; % 风向与观测向夹角U10 = 12; % 10米高处海面风速 %
5m/s, 10m/s, 15m/s 的风浪谱宽度分别为 1.5, 0.4, 0.15.对应的最大空间采样间隔为2m, 10m,
20mKwindPeak = g / ( 1.2 * U10 )^2;% sea wave spectrum parameterNxSeaWave = xNs;
% 频域采样点数,方便傅立叶变换NySeaWave = yNs; KxSeaWave = 2 * pi / SeaRegLx * ( -xNs
/ 2 : 1 : xNs / 2 - 1 );KySeaWave = 2 * pi / SeaRegLy * ( -yNs / 2 : 1 : yNs / 2
- 1 );KxSeaWaveTicks = KxSeaWave;KySeaWaveTicks = KySeaWave;KxSeaWave = (
KxSeaWave == 0 ) * ( max( KxSeaWave ) * 1e-16 ) + KxSeaWave; % avoid divided by
0KySeaWave = ( KySeaWave == 0 ) * ( max( KySeaWave ) * 1e-16 ) + KySeaWave; %
avoid divided by 0% swell wave spectrumSpectrumSwell = zeros( NySeaWave,
NxSeaWave );Temp1 = ones( NySeaWave, 1 ) * ( KxSeaWave - KxswellWavePeak ) /
SigmaKx;Temp2 = ( KySeaWave - KyswellWavePeak )' / SigmaKy * ones( 1, NxSeaWave
);SpectrumSwell = SigmaHSwell^2 / 2 / pi / SigmaKx / SigmaKy * exp( -0.5 * (
Temp1.^2 + Temp2.^2 ) );clear Temp1;clear Temp2;figure;colormap(gray(256));image(
KxSeaWave, KySeaWave, 256 - 255 / ( max( max( abs( SpectrumSwell ) ) ) - min( min
( abs( SpectrumSwell ) ) ) ) * ( abs( SpectrumSwell ) - min( min ( abs(
SpectrumSwell ) ) ) ) );axis('xy');xlabel( 'kx:X方向波数');ylabel( 'ky:Y方向波
数');title( '涌浪谱');KxSeaWaveMatrix = ones( NySeaWave, 1 ) *
KxSeaWave;KySeaWaveMatrix = KySeaWave' * ones( 1, NxSeaWave );KSeaWaveTemp1 = (
sqrt( KxSeaWaveMatrix.^2 + KySeaWaveMatrix.^2 ) );Fwk1 = exp( - 1.22 * ( sqrt(
KSeaWaveTemp1 ./ KwindPeak ) -1 ).^2 );HKKpx1 = 1.24 * ( ( KSeaWaveTemp1 /
KwindPeak < 0.31 ) & ( KSeaWaveTemp1 / KwindPeak >= 0 ) );HKKpx2 = 2.61 * ( (
KSeaWaveTemp1 / KwindPeak ).^0.65 ) .* ( ( KSeaWaveTemp1 / KwindPeak < 0.9 ) & (
KSeaWaveTemp1 / KwindPeak >= 0.31 ) );HKKpx3 = 2.28 * ( ( KSeaWaveTemp1 /
KwindPeak ).^( -0.65 ) ) .* ( KSeaWaveTemp1 / KwindPeak >= 0.9 );HKKp1 = HKKpx1 +
HKKpx2 + HKKpx3;Temp1x = 1.62 * 1e-3 * U10 / ( g^0.5 ) ./ ( KSeaWaveTemp1
).^3.5;Temp2x = exp( -( KwindPeak ./ KSeaWaveTemp1 ).^2 ) .* ( 1.7 .^ Fwk1
);Temp3x = ( HKKp1 .* ( sech( ( HKKp1 .* ( atan( ( KySeaWaveMatrix ./
KxSeaWaveMatrix ) ) - WindAngle ) ) ) ).^2 );% SpectrumWind1 = ( Temp1x .* Temp2x
.* Temp3x )';% SpectrumWind = SpectrumWind1';SpectrumWind = Temp1x .* Temp2x .*
Temp3x;clear KSeaWaveTemp1 Fwk1 HKKpx1 HKKpx2 HKKpx3 HKKp1 Temp1x Temp2x
Temp3x;figure;contour( KxSeaWave, KySeaWave, abs( SpectrumWind )
);axis('xy');xlabel( 'kx:X方向波数');ylabel( 'ky:Y方向波数');title( '风浪
谱');%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%全谱= 涌浪谱+风
浪谱SpectrumSea = SpectrumSwell + SpectrumWind;% 用于产生海面仿真的真实海浪谱,叠加了随
机因素% 产生均值为1的瑞利分布和均匀相位分布rand('state',sum(100*clock));PhiSeaRand = 2
* pi * rand( NySeaWave, NxSeaWave );AmRayleigh = raylrnd( 1, NySeaWave, NxSeaWave
);SpectrumSeaReal = 2 * pi .* sqrt( 2 * xNs * yNs / xSampleStep / ySampleStep .*
SpectrumSea ) .* AmRayleigh .* exp( j * PhiSeaRand );% 海面高度wh = zeros( yNs,
xNs ); % Wave Height, heigth depart from mean sea level% wh = real( ( fftshift(
fft( ( fftshift( fftshift( fft( fftshift( SpectrumSeaReal ), yNs ) ) ) )', xNs )
) )' ) / NySeaWave / NxSeaWave;wh = ( fftshift( fft( ( fftshift( fftshift( fft(
fftshift( SpectrumSeaReal ), yNs ) ) ) )', xNs ) ) )' / NySeaWave /
NxSeaWave;Varwh = sqrt( sum( sum( ( real( wh ) - mean( mean( real( wh ) ) ) ).^2
) ) / xNs / yNs );wh = wh / Varwh * ( SigmaHSwell / 2 );% 用涌浪波高进行归一化hFig =
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