在MATLAB R2014a中，以下两个代码文件起作用：
chan = RicianChannel(1/bitrate,100,8);
chan = comm.RicianChannel(1/bitrate,100,8);
然而，在R2021a中，它们不再这样做了。更新后的语法是什么？
ricianchan = comm.RicianChannel( ...
'SampleRate',1e6, ...
'PathDelays',[0.0 0.5 1.2]*1e-6, ...
'AveragePathGains',[0.1 0.5 0.2], ...
'KFactor',2.8, ...
'DirectPathDopplerShift',5.0, ...
'DirectPathInitialPhase',0.5, ...
'MaximumDopplerShift',50, ...
'DopplerSpectrum',doppler('Bell', 8), ...
'RandomStream','mt19937ar with seed', ...
'Seed',73, ...
'PathGainsOutputPort',true);```