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软件无线电的平台

chest
=====


Channel knowledge is necessary for the detection of symbols in a MIMO
receiver. Knowledge of channel is gained by sending a known training
sequence. This traininig sequence satisfies certain desired properties
as given by 1) Jaiganesh Balakrishnan, Markus Rupp, Harish Viswanthan
'Optimal Training for Multiple Antenna Systems' 2)C.Fragouli, N. Al-Dhahir,
W. Turin 'Training based channel estimation for Multiple Antenna Brodband
Transmissions'. Please refer to them for more technical details.


chest_rcv
---------

 Using the midamble the channel is estimated for the given antenna. This module also removes
 the midamble part of the data stream.

Inputs:
	SYMBOL_COMPLEX

outputs:
	SYMBOL_COMPLEX

Config:
	align<int>: 0
		0-> don't move the signal
		else align output to the strongest tap of channel "align"
		if calc_taps > 0, then align means that the number of taps calculated
		are 'around' the peak of the channel impulse response.

	calc_taps<int>: 0
		How many taps shall be used in the channel equalisation. If you
		want to use the signal for some decoding, this is best left to
		0 (which means the signal won't be altered and you only get a channel
		estimation). If there is some hard-decision, put it to 1 or more

	circ_ext<int>: 8
		The length of the circular extension

	index<int>: 0
		The midamble-index for this chest

	num_of_antennas<int>: 1
		Necessary for noise variance estimation, represnts no. Tx antennas

	type<int>: 0
		0-> MCCDMA, 1 -> Fra


Stats:
	ch_length<int>:
		The length of the channel impulse response

	channel<block_t>:
		The channel of all N received antennas

	channel_inv<block_t>:
		The inversed channel

	mid_amp<int>:
		mean midamble-amplitude

	midamble<block_t>:
		The midamble

	noise_var<int>:
		The general noise variance = Realpart+Imagpart

	noise_var_imag<int>:
		Imag part

	noise_var_real<int>:
		Real part

	peak_amp<int>:
		peak-amplitude of the midamble

	peak_pos<int>:
		The peak of the midamble

	snr<double>:
		The SNR in db


chest_rcv_mimo
--------------

 Using the midamble the channel is estimated for the given antenna. This module
also removes the midamble part of the data stream.
 It does assume that there are a maximum of training_seq[].M senders, and that 
each sender has an increasing index. This means that a sender has at most
training_seq[].L channel taps.
 Each output corresponds to one sender. So, if you want to receive sender #2,
connect to output #2

Inputs:
	SYMBOL_COMPLEX

outputs:
	SYMBOL_COMPLEX

Config:
	align<int>: 1
		0-> don't move the signal
		else align output to the strongest tap of channel "align"
		if calc_taps > 0, then align means that the number of taps calculated
		are 'around' the peak of the channel impulse response.

	calc_taps<int>: 4
		How many taps shall be used in the channel equalisation. If you
		want to use the signal for some decoding, this is best left to
		0 (which means the signal won't be altered and you only get a channel
		estimation). If there is some hard-decision, put it to 1 or more

	circ_ext<int>: 8
		The length of the circular extension

	num_of_antennas<int>: 1
		Necessary for noise variance estimation, represnts no. Tx antennas

	type<int>: 0
		0-> MCCDMA, 1 -> Fra


Stats:
	ch_length<int>:
		The length of the channel impulse response

	channel<block_t>:
		The channel of all N received antennas

	channel_inv<block_t>:
		The inversed channel

	mid_amp<int>:
		mean midamble-amplitude

	midamble<block_t>:
		The midamble

	noise_var<int>:
		The general noise variance = Realpart+Imagpart

	noise_var_imag<int>:
		Imag part

	noise_var_real<int>:
		Real part

	peak_amp<int>:
		peak-amplitude of the midamble

	peak_pos<int>:
		The peak of the midamble

	snr<double>:
		The SNR in db


chest_rcv_mimo_ics
------------------

  Mimo Channel Estimation is done in the module
  Also the Midambles are removed

Inputs:
	SYMBOL_COMPLEX

outputs:
	SYMBOL_COMPLEX

Config:
	align<int>: 0
		0-> don't move the signal
		else align output to the strongest tap of channel "align"
		if calc_taps > 0, then align means that the number of taps calculated
		are 'around' the peak of the channel impulse response.

	calc_taps<int>: 0
		How many taps shall be used in the channel equalisation. If you
		want to use the signal for some decoding, this is best left to
		0 (which means the signal won't be altered and you only get a channel
		estimation). If there is some hard-decision, put it to 1 or more

	circ_ext<int>: 8
		The length of the circular extension

	index<int>: 0
		The midamble-index for this chest

	num_of_antennas<int>: undef
		Necessary for noise variance estimation, represnts no. Tx antennas

	type<int>: undef
		0-> MCCDMA, 1 -> Fra


Stats:
	ch_length<int>:
		The length of the channel impulse response

	channel<block_t>:
		The channel of all N received antennas

	channel_inv<block_t>:
		The inversed channel

	mid_amp<int>:
		mean midamble-amplitude

	midamble<block_t>:
		The midamble

	noise_var<int>:
		The general noise variance = Realpart+Imagpart

	noise_var_imag<int>:
		Imag part

	noise_var_real<int>:
		Real part

	peak_amp<int>:
		peak-amplitude of the midamble

	peak_pos<int>:
		The peak of the midamble

	snr<double>:
		The SNR in db

	transfer_matrix<block_t>:
		The peaks corresponding to the NO_RX channels


chest_send
----------

Midamble insertion module, MIMO incorporated!

Inputs:
	SYMBOL_COMPLEX

outputs:
	SYMBOL_COMPLEX

Config:
	amplitude<int>: 32767
		The amplitude of the midamble

	circ_ext<int>: 8
		How many samples for the circular extension

	index<int>: 0
		Antenna index

	type<int>: 0
		The type of the midamble inserted:
		0-> MCCDMA
		1-> Fra