berr_perfect.m File Reference

Functions
1/sqrt(2	modvec_bpsk ()
mod_fcn_16qam, tx_data	arrayfun ()
otherwise	fprintf ('Invalid MOD_ORDER(%d)! Must be in[2, 4, 16, 64]\n', MOD_ORDER)
	CN (0, nvar)
	switch (MOD_ORDER) case 2 % BPSK rx_data

Variables
function	berr_th
	tx_data = randi(MOD_ORDER, N_DATA_SYMS, 1) - 1
	modvec_16qam = (1/sqrt(10)) .* [-3 -1 +3 +1]
	modvec_64qam = (1/sqrt(42)) .* [-7 -5 -1 -3 +7 +5 +1 +3]
	mod_fcn_bpsk = @(x) complex(modvec_bpsk(1+x),0)
	mod_fcn_qpsk = @(x) complex(modvec_bpsk(1+bitshift(x, -1)), modvec_bpsk(1+mod(x, 2)))
	mod_fcn_16qam = @(x) complex(modvec_16qam(1+bitshift(x, -2)), modvec_16qam(1+mod(x,4)))
	mod_fcn_64qam = @(x) complex(modvec_64qam(1+bitshift(x, -3)), modvec_64qam(1+mod(x,8)))
Map the data values on to complex symbols switch MOD_ORDER case BPSK	tx_syms = arrayfun(mod_fcn_bpsk, tx_data)
	return
end Create channel if	awgn
	h = sqrt(hvar/2).*(randn(N_DATA_SYMS, N_ANT) + 1i*randn(N_DATA_SYMS, N_ANT))
end Add noise	nvar = 1/ 10^(0.1*snr)
	w = sqrt(nvar/2).*(randn(N_DATA_SYMS,1) + 1i*randn(N_DATA_SYMS,1))
	rx_syms = h.*tx_syms + w
Equalize with *known *	channel
Demodulate	demod_fcn_bpsk = @(x) double(real(x)>0)
	demod_fcn_qpsk = @(x) double(2*(real(x)>0) + 1*(imag(x)>0))
	demod_fcn_16qam = @(x) (8*(real(x)>0)) + (4*(abs(real(x))<0.6325)) + (2*(imag(x)>0)) + (1*(abs(imag(x))<0.6325))
	demod_fcn_64qam
case QPSK	rx_data = arrayfun(demod_fcn_qpsk, syms_eq)
end Error rates	nbits = N_DATA_SYMS * log2(MOD_ORDER)
	bit_errs = length(find(dec2bin(bitxor(tx_data, rx_data),8) == '1'))

Function Documentation

arrayfun()

demod_fcn_64qam syms_eq arrayfun ( )

virtual

CN()

CN	(	0	,
		nvar
	)

fprintf()

otherwise fprintf	(	'Invalid MOD_ORDER(%d)! Must be in\n'	[2, 4, 16, 64],
		MOD_ORDER
	)

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modvec_bpsk()

1/sqrt(2 modvec_bpsk ( )

virtual

switch()

switch

(

MOD_ORDER

)

Variable Documentation

awgn

end Create channel if awgn

Initial value:

== 0
    hvar = 1

berr_th

berr_th

Initial value:

= berr_perfect(snr, N_ANT,MOD_ORDER, awgn)
% Theoretical BER with no chan. est error.
 
N_DATA_SYMS = 1e5

bit_errs

bit_errs = length(find(dec2bin(bitxor(tx_data, rx_data),8) == '1'))

channel

Equalize with* known* channel

demod_fcn_16qam

demod_fcn_16qam = @(x) (8*(real(x)>0)) + (4*(abs(real(x))<0.6325)) + (2*(imag(x)>0)) + (1*(abs(imag(x))<0.6325))

demod_fcn_64qam

demod_fcn_64qam

Initial value:

= @(x) (32*(real(x)>0)) + (16*(abs(real(x))<0.6172)) + ... 
    (8*((abs(real(x))<(0.9258))&&((abs(real(x))>(0.3086))))) + ...
    (4*(imag(x)>0)) + (2*(abs(imag(x))<0.6172)) + ...
    (1*((abs(imag(x))<(0.9258))&&((abs(imag(x))>(0.3086)))))

demod_fcn_bpsk

Demodulate demod_fcn_bpsk = @(x) double(real(x)>0)

demod_fcn_qpsk

demod_fcn_qpsk = @(x) double(2*(real(x)>0) + 1*(imag(x)>0))

h

else h = sqrt(hvar/2).*(randn(N_DATA_SYMS, N_ANT) + 1i*randn(N_DATA_SYMS, N_ANT))

mod_fcn_16qam

mod_fcn_16qam = @(x) complex(modvec_16qam(1+bitshift(x, -2)), modvec_16qam(1+mod(x,4)))

mod_fcn_64qam

mod_fcn_64qam = @(x) complex(modvec_64qam(1+bitshift(x, -3)), modvec_64qam(1+mod(x,8)))

mod_fcn_bpsk

mod_fcn_bpsk = @(x) complex(modvec_bpsk(1+x),0)

mod_fcn_qpsk

mod_fcn_qpsk = @(x) complex(modvec_bpsk(1+bitshift(x, -1)), modvec_bpsk(1+mod(x, 2)))

modvec_16qam

modvec_16qam = (1/sqrt(10)) .* [-3 -1 +3 +1]

modvec_64qam

modvec_64qam = (1/sqrt(42)) .* [-7 -5 -1 -3 +7 +5 +1 +3]

nbits

end Error rates nbits = N_DATA_SYMS * log2(MOD_ORDER)

nvar

end Add noise nvar = 1/ 10^(0.1*snr)

return

return

rx_data

case QPSK rx_data = arrayfun(demod_fcn_qpsk, syms_eq)

rx_syms

rx_syms = h.*tx_syms + w

tx_data

tx_data = randi(MOD_ORDER, N_DATA_SYMS, 1) - 1

tx_syms

case QPSK tx_syms = arrayfun(mod_fcn_bpsk, tx_data)

w

w = sqrt(nvar/2).*(randn(N_DATA_SYMS,1) + 1i*randn(N_DATA_SYMS,1))