diff options
| author | Tim O'Shea <tim.oshea753@gmail.com> | 2013-11-08 12:44:37 -0500 |
|---|---|---|
| committer | Tim O'Shea <tim.oshea753@gmail.com> | 2013-11-08 12:44:37 -0500 |
| commit | 917fb98fdd6f706a58dae515fc0e28fa5ac3b906 (patch) | |
| tree | 77c476257f7387b4a4b8b32ae0b061b43801aa4d /gr-channels/grc | |
| parent | 173b9fc9785cc2f8d11bbd965ca56e05e4e4e3e0 (diff) | |
channels: new block documentation/grc cleanup, dynamic fading model AWGN ampl bug fix
Diffstat (limited to 'gr-channels/grc')
| -rw-r--r-- | gr-channels/grc/channels_block_tree.xml | 3 | ||||
| -rw-r--r-- | gr-channels/grc/channels_dynamic_channel_model.xml | 32 |
2 files changed, 9 insertions, 26 deletions
diff --git a/gr-channels/grc/channels_block_tree.xml b/gr-channels/grc/channels_block_tree.xml index 154e9204d1..66053f717d 100644 --- a/gr-channels/grc/channels_block_tree.xml +++ b/gr-channels/grc/channels_block_tree.xml @@ -32,6 +32,7 @@ <name>Channel Models</name> <block>channels_channel_model</block> <block>channels_fading_model</block> + <block>channels_dynamic_channel_model</block> </cat> <cat> <name>Impairment Models</name> @@ -43,5 +44,7 @@ <block>channels_distortion_3_gen</block> <block>channels_amp_bal</block> <block>channels_phase_bal</block> + <block>channels_cfo_model</block> + <block>channels_sro_model</block> </cat> </cat> diff --git a/gr-channels/grc/channels_dynamic_channel_model.xml b/gr-channels/grc/channels_dynamic_channel_model.xml index b87b40da11..b54256c864 100644 --- a/gr-channels/grc/channels_dynamic_channel_model.xml +++ b/gr-channels/grc/channels_dynamic_channel_model.xml @@ -118,32 +118,12 @@ <type>complex</type> </source> <doc> - int d_N=8; // number of sinusoids used to simulate gain on each ray - float d_fDTs=0.01 // normalized maximum doppler frequency (f_doppler / f_samprate) - float d_K=4; // Rician factor (ratio of the specular power to the scattered power) - bool d_LOS=true; // LOS path exists? chooses Rician (LOS) vs Rayleigh (NLOS) model. - int seed=0; // noise seed - int ntaps; // Number of FIR taps to use in selective fading model - - These two vectors comprise the Power Delay Profile of the signal - float_vector delays // Time delay in the fir filter (in samples) for each arriving WSSUS Ray - float_vector mags // Magnitude corresponding to each WSSUS Ray + The dynamic channel model is a hier block consisting of the following effects: + - Dynamic Frequency Selective Fading Channel + - Dynamic Center Frequency Offset Model + - Dynamic Sample Rate Offset Model + - Additive White Gaussian Noise - If using a LOS model, the first delay and mag should correspond with the LOS component - - References: - - The flat-fading portion of the algorithm implements the following - Compact Rayleigh and Rician fading simulator based on random walk processes - A. Alimohammad S.F. Fard B.F. Cockburn C. Schlegel - 26th November 2008 - - The frequency selective extension of the block roughly implements - A Low-Complexity Hardware Implementation of Discrete-Time - Frequency-Selective Rayleigh Fading Channels - F. Ren and Y. Zheng - 24-27 May 2009 - - Implementation by Tim O'Shea + The desired power delay profile and max doppler frequency may be provided to achieve the desired Ricean or Rayleigh fading scenario. For center frequency and sample rate offset models, a gaussian random walk process is conducted for each. The single sample step variance and maximum deviation for these two processes is specified and may be modified to simulate various desired stability effects. Lastly AWGN is added to simulate a typical receiver/thermal noise floor after propagation, and the variance may be modified here as desired. </doc> </block> |