function?[htt0np]?=?uwb_sv_model_ct（Lam?lambda?Gam?gamma?std_ln_1?std_ln_2?nlos?...
??????????????????????????std_shdw?num_channels）
%?IEEE?802.15.3a?UWB?channel?model?for?PHY?proposal?evaluation
%??????continuous-time?realization?of?modified?S-V?channel?model
%?Input?parameters:
%???Lam??????Cluster?arrival?rate?in?GHz?（avg?#?of?clusters?per?nsec）
%???lambda???Ray?arrival?rate?in?GHz?（avg?#?of?rays?per?nsec）
%???Gam??????Cluster?decay?factor?（time?constant?nsec）
%???gamma????Ray?decay?factor?（time?constant?nsec）
%???std_ln_1?Standard?deviation?of?log-normal?variable?for?cluster?fading
%???std_ln_2?Standard?deviation?of?log-normal?variable?for?ray?fading
%???nlos?????Flag?to?specify?generation?of?Non?Line?Of?Sight?channels
%???std_shdw??Standard?deviation?of?log-normal?shadowing?of?entire?impulse?response
%???num_channels??number?of?random?realizations?to?generate
%?Outputs
%???h?is?returned?as?a?matrix?with?num_channels?columns?each?column?
%?????holding?a?random?realization?of?the?channel?model?（an?impulse?response）
%???t?is?organized?as?h?but?holds?the?time?instances?（in?nsec）?of?the?paths?whose
%?????signed?amplitudes?are?stored?in?h
%???t0?is?the?arrival?time?of?the?first?cluster?for?each?realization
%???np?is?the?number?of?paths?for?each?realization.
%?Thus?the?k‘th?realization?of?the?channel?impulse?response?is?the?sequence?
%???of?（timevalue）?pairs?given?by?（t（1:np（k）k）?h（1:np（k）k））

%?initialize?and?precompute?some?things
std_L?=?1/sqrt（2*Lam）;??????%?std?dev?（nsec）?of?cluster?arrival?spacing
std_lam?=?1/sqrt（2*lambda）;?%?std?dev?（nsec）?of?ray?arrival?spacing
mu_const?=?（std_ln_1^2+std_ln_2^2）*log（10）/20;??%?pre-compute?for?later
h_len?=?1000;??%?there?must?be?a?better?estimate?of?#?of?paths?than?this
ngrow?=?1000;?%?amount?to?grow?data?structure?if?more?paths?are?needed
h?=?zeros（h_lennum_channels）;
t?=?zeros（h_lennum_channels）;
t0?=?zeros（1num_channels）;
np?=?zeros（1num_channels）;

for?k?=?1:num_channels???