generate_data_dl.m File Reference

Functions
	pilot_f (pilot_f==0)
	pilot_f (setdiff(1:N_SC, SC_IND_DATA))=0
	fwrite (fileID, pilot_f, 'float')
	fclose (fileID)
	fwrite (fileID, pilot_t, 'float')
	fwrite (fileID_data, tx_data_for_saving(:), 'uint8')
	fclose (fileID_data)
mod_fcn_16qam, tx_data	arrayfun ()
otherwise	fprintf ('Invalid MOD_ORDER(%d)! Must be in[2, 4, 16]\n', MOD_ORDER)
end IFFT Reshape the symbol vector into two different spatial streams	length (tx_syms)/NUM_UE
	tx_syms_mat (SC_IND_DATA,:,:)
	ifft_in_mat_A (SC_IND_PILOTS, :)
Add CP Insert the cyclic prefix	if (CP_LEN > 0) tx_cp
2	sqrt ()
	H_vec_float (1:2:end)
	H_vec_float (2:2:end)
	fwrite (fileID, H_vec_float, 'float')
N_SC, NUM_UE, NUM_UE	zeros ()
	CSI_est (:, i,:)
end	fprintf ("CSI_estimation error: %d/%d\n", sum(sum(sum(abs(CSI_est(SC_IND_DATA,:,:) -H_noisy(SC_IND_DATA,:,:))>0.5 *1e-1))), length(H_noisy(:)))
	rx_vec_float (1:2:end)
	rx_vec_float (2:2:end)
	fwrite (fileID, rx_vec_float, 'float')
	rx_syms_mat (i,:,:)
	switch (MOD_ORDER) case 2 % BPSK rx_data
	fprintf ("Uplink: correct data demodulation: %d/%d\n", sum(sum(sum(rx_data==tx_data_mat))), length(tx_data_mat(:)))
show data of symbol and all users from subcarrier to	disp (squeeze(rx_data(1:6, 1,:)))
Reshape to a vector	numel (tx_payload_mat))
pilot_t.', 1, NUM_UE	tx_payload_vec ()
Downlink data analysis	fprintf ("Downlink.....\n")
end	fprintf ("CSI_estimation error: %d/%d\n", sum(sum(sum(abs(CSI_est(SC_IND_DATA,:,:) -H_from_file_float(SC_IND_DATA,:,:))>0.5 *1e-1))), length(H_from_file_float(:)))
	precoder_from_file (i,:,:)
	dl_rx_data_f (OFDM_START_OFFSET+i,:,:)
	dl_rx_data_f (424+i,:,:)
	dl_rx_data_saving_float (1:2:end)
	dl_rx_data_saving_float (2:2:end)
	fwrite (fileID, dl_rx_data_saving_float, 'float')
	fprintf ("Downlink: correct data demodulation: %d/%d\n", sum(sum(sum(ue_rx_data==tx_data_dl_raw))), length(SC_IND_DATA) *NUM_UE *(N_SYMS-NUM_UE))

Variables
Parameters	MOD_ORDER = 16
	N_SC = 2048
	SC_IND_DATA = 425:1624
	OFDM_START_OFFSET = 424
	NUM_BS_ANT = 8
	NUM_UE = 8
	N_SYMS = 70
	N_OFDM_SYMS = (N_SYMS-NUM_UE)*NUM_UE
	N_DATA_SYMS = N_OFDM_SYMS * length(SC_IND_DATA)
used to generate new pilot files in time domain and frequency domain pilot in time	domain
used to generate new data files original data(tx_data) for all users before modulation	CP_LEN = 0
	frmLen = 100
frame length Generate pilot if GENERATE_PILOT	pilot_f = randi(3,N_SC,1)-2
	pilot_t = ifft(pilot_f, N_SC)
	fileID = fopen('../files/experiment/pilot_f_2048.bin','w')
end Generate data if GENERATE_DATA	tx_data = randi(MOD_ORDER, 1, N_DATA_SYMS) - 1
	tx_data_for_saving = reshape(tx_data, length(SC_IND_DATA), N_OFDM_SYMS/NUM_UE, NUM_UE)
	fileID_data = fopen(sprintf('../files/experiment/orig_data_2048_ant%d.bin',NUM_BS_ANT),'w')
end Modulate data	modvec_bpsk = (1/sqrt(2)) .* [-1 1]
	modvec_16qam = (1/sqrt(10)) .* [-3 -1 +3 +1]
	getbit13 = @(x) (bitget(x,3) * 2 + bitget(x,1))
	getbit24 = @(x) (bitget(x,4) * 2 + bitget(x,2))
	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)))
switch MOD_ORDER case BPSK	tx_syms = arrayfun(mod_fcn_bpsk, tx_data)
	return
end IFFT Reshape the symbol vector into two different spatial streams	size
Construct the IFFT input matrix	ifft_in_mat = zeros(NUM_BS_ANT, N_SC, N_OFDM_SYMS/NUM_BS_ANT)
Insert the data and pilot	values
Perform the IFFT	tx_payload_mat = ifft(ifft_in_mat, N_SC, 1)
	H = repmat(H,1,1,N_SC)
	noise = (randn(N_SC,NUM_UE, NUM_BS_ANT) + 1i*randn(N_SC, NUM_UE, NUM_BS_ANT))/sqrt(2)/100
	H_noisy = H + noise
	H_vec = reshape(H_noisy, 1, numel(H_noisy))
	H_vec_float = zeros(1,size(H_vec,2)*2)
	H_from_file = fread(fileID,[1,N_SC*NUM_UE*NUM_BS_ANT*2],'float')
for	i
end	pilot_all_ue = reshape(pilot_all_ue, N_SC,1,NUM_UE)
	tx_mat_all = cat(2,pilot_all_ue,tx_payload_mat)
	tx_mat = reshape(tx_mat_all,N_SC*N_SYMS,NUM_UE)
Rx data	rx_mat_all = zeros(N_SC,N_SYMS,NUM_BS_ANT)
	tx_mat_all_f = fft(tx_mat_all,N_SC,1)
	rx_mat_all_f = zeros(N_SC,N_SYMS,NUM_BS_ANT)
	rx_mat = tx_mat*H
CSI estimation	CSI_est = zeros(N_SC,NUM_UE,NUM_BS_ANT)
	pilot_est = zeros(N_SC,NUM_UE,NUM_BS_ANT)
	rx_vec = reshape(rx_mat_all, 1, numel(rx_mat_all))
	rx_vec_float = zeros(1,size(rx_vec,2)*2)
end	H_est = squeeze(CSI_est(1,:,:))
	rx_data_fft = fft(rx_mat_data,N_SC,1)
	precoder_all = zeros(length(SC_IND_DATA),NUM_BS_ANT,NUM_UE)
	rx_syms_mat = zeros(length(SC_IND_DATA),N_SYMS-NUM_UE,NUM_UE)
	rx_mat_data = rx_mat_all(:,:,NUM_UE+1:end)
size	__pad1__
	rx_syms = precoder * rx_data_fft
	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))
case QPSK	rx_data = arrayfun(demod_fcn_qpsk, rx_syms_mat(:))
	tx_data_mat = reshape(tx_data,length(SC_IND_DATA),N_SYMS-NUM_UE,NUM_UE)
	rx_data_from_file = fread(fileID,[1,N_SC*N_SYMS*NUM_BS_ANT*2],'float')
	rx_data_from_file_float = rx_data_from_file(1:2:end)+1j*rx_data_from_file(2:2:end)
	rx_pilot_from_file = rx_data_from_file_float(:,1:8,:)
	H_from_file_float = H_from_file(1:2:end)+1j*H_from_file(2:2:end)
Precoder calculation and precoding	precoder_from_file = zeros(N_SC,NUM_BS_ANT,NUM_UE)
end original data before modulation	tx_data_dl_raw = reshape(tx_data,length(SC_IND_DATA),N_SYMS-NUM_UE, NUM_UE)
original data after modulation	tx_data_dl = reshape(tx_syms,length(SC_IND_DATA),N_SYMS-NUM_UE, NUM_UE)
	precoded_data = zeros(N_SC,NUM_BS_ANT,N_SYMS-NUM_UE)
	dl_rx_data_f = zeros(N_SC,NUM_BS_ANT,N_SYMS-NUM_UE)
end	ifft_data = ifft(precoded_data,N_SC,1)
	dl_rx_data = ifft(dl_rx_data_f,N_SC,1)
if GENERATE_DATA	dl_rx_data_saving = dl_rx_data(:).* N_SC
	dl_rx_data_saving_float = zeros(1,length(dl_rx_data_saving)*2)
end	dl_rx_data_fft_orig = fft(dl_rx_data,N_SC,1)
	dl_rx_data_fft = zeros(length(SC_IND_DATA),NUM_UE,N_SYMS-NUM_UE)
case QPSK	ue_rx_data = arrayfun(demod_fcn_qpsk, dl_rx_data_fft(:))

Function Documentation

arrayfun()

mod_fcn_16qam, tx_data arrayfun ( )

virtual

CSI_est()

CSI_est	(	:	,
		i	,
		:
	)

disp()

show data of symbol and all users from subcarrier to disp

(

squeeze(rx_data(1:6, 1,:))

)

dl_rx_data_f() [1/2]

dl_rx_data_f	(	424+	i,
		:	,
		:
	)

dl_rx_data_f() [2/2]

dl_rx_data_f	(	OFDM_START_OFFSET+	i,
		:	,
		:
	)

dl_rx_data_saving_float() [1/2]

dl_rx_data_saving_float

(

1:2:end

)

dl_rx_data_saving_float() [2/2]

dl_rx_data_saving_float

(

2:2:end

)

fclose() [1/2]

fclose

(

fileID

)

fclose() [2/2]

fclose

(

fileID_data

)

fprintf() [1/6]

end fprintf	(	"CSI_estimation error: %d/%d\n"	,
		sum(sum(sum(abs(CSI_est(SC_IND_DATA,:,:) -H_from_file_float(SC_IND_DATA,:,:))>0.5 *1e-1)))	,
		length(H_from_file_float(:))
	)

fprintf() [2/6]

end fprintf	(	"CSI_estimation error: %d/%d\n"	,
		sum(sum(sum(abs(CSI_est(SC_IND_DATA,:,:) -H_noisy(SC_IND_DATA,:,:))>0.5 *1e-1)))	,
		length(H_noisy(:))
	)

fprintf() [3/6]

Downlink data analysis fprintf

(

"Downlink.....\n"

)

fprintf() [4/6]

fprintf	(	"Downlink: correct data demodulation: %d/%d\n"	,
		sum(sum(sum(ue_rx_data==tx_data_dl_raw)))	,
		length(SC_IND_DATA) *NUM_UE *(N_SYMS-NUM_UE)
	)

fprintf() [5/6]

fprintf	(	"Uplink: correct data demodulation: %d/%d\n"	,
		sum(sum(sum(rx_data==tx_data_mat)))	,
		length(tx_data_mat(:))
	)

fprintf() [6/6]

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

fwrite() [1/6]

fwrite	(	fileID	,
		dl_rx_data_saving_float	,
		'float'
	)

fwrite() [2/6]

fwrite	(	fileID	,
		H_vec_float	,
		'float'
	)

fwrite() [3/6]

fwrite	(	fileID	,
		pilot_f	,
		'float'
	)

fwrite() [4/6]

fwrite	(	fileID	,
		pilot_t	,
		'float'
	)

fwrite() [5/6]

fwrite	(	fileID	,
		rx_vec_float	,
		'float'
	)

fwrite() [6/6]

fwrite	(	fileID_data	,
		tx_data_for_saving(:)	,
		'uint8'
	)

H_vec_float() [1/2]

H_vec_float

(

1:2:end

)

H_vec_float() [2/2]

H_vec_float

(

2:2:end

)

if()

Add CP Insert the cyclic prefix if	(	CP_LEN	,
		0
	)

ifft_in_mat_A()

ifft_in_mat_A	(	SC_IND_PILOTS	,
		:
	)

length()

end IFFT Reshape the symbol vector into two different spatial streams length

(

tx_syms

)

numel()

Reshape to a vector numel

(

tx_payload_mat

)

pilot_f() [1/2]

pilot_f

(

pilot_f

= =0

)

pilot_f() [2/2]

pilot_f ( setdiff(1:N_SC, SC_IND_DATA)  )

pure virtual

precoder_from_file()

precoder_from_file	(	i	,
		:	,
		:
	)

rx_syms_mat()

rx_syms_mat	(	i	,
		:	,
		:
	)

rx_vec_float() [1/2]

rx_vec_float

(

1:2:end

)

rx_vec_float() [2/2]

rx_vec_float

(

2:2:end

)

sqrt()

2 sqrt ( )

staticvirtual

switch()

switch

(

MOD_ORDER

)

tx_payload_vec()

pilot_t.',1,NUM_UE tx_payload_vec ( )

virtual

tx_syms_mat()

tx_syms_mat	(	SC_IND_DATA	,
		:	,
		:
	)

zeros()

N_SC,NUM_UE,NUM_UE zeros ( )

staticvirtual

Variable Documentation

__pad1__

size __pad1__

CP_LEN

used to generate new data files original data (tx_data) for all users before modulation CP_LEN = 0

CSI_est

CSI estimation CSI_est = zeros(N_SC,NUM_UE,NUM_BS_ANT)

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_bpsk

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

demod_fcn_qpsk

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

dl_rx_data

dl_rx_data = ifft(dl_rx_data_f,N_SC,1)

dl_rx_data_f

dl_rx_data_f = zeros(N_SC,NUM_BS_ANT,N_SYMS-NUM_UE)

dl_rx_data_fft

demod_fcn_16qam dl_rx_data_fft = zeros(length(SC_IND_DATA),NUM_UE,N_SYMS-NUM_UE)

dl_rx_data_fft_orig

end dl_rx_data_fft_orig = fft(dl_rx_data,N_SC,1)

dl_rx_data_saving

if GENERATE_DATA dl_rx_data_saving = dl_rx_data(:).* N_SC

dl_rx_data_saving_float

dl_rx_data_saving_float = zeros(1,length(dl_rx_data_saving)*2)

domain

used to generate new pilot files in time domain and frequency domain pilot in time domain

fileID

fileID = fopen('../files/experiment/pilot_f_2048.bin','w')

fileID_data

else fileID_data = fopen(sprintf('../files/experiment/orig_data_2048_ant%d.bin',NUM_BS_ANT),'w')

frmLen

frmLen = 100

getbit13

getbit13 = @(x) (bitget(x,3) * 2 + bitget(x,1))

getbit24

getbit24 = @(x) (bitget(x,4) * 2 + bitget(x,2))

H

H = repmat(H,1,1,N_SC)

H_est

end H_est = squeeze(CSI_est(1,:,:))

H_from_file

H_from_file = fread(fileID,[1,N_SC*NUM_UE*NUM_BS_ANT*2],'float')

H_from_file_float

H_from_file_float = H_from_file(1:2:end)+1j*H_from_file(2:2:end)

H_noisy

H_noisy = H + noise

H_vec

H_vec = reshape(H_noisy, 1, numel(H_noisy))

H_vec_float

H_vec_float = zeros(1,size(H_vec,2)*2)

i

for i

Initial value:

= 1:NUM_UE
    pilot_all_ue(:,i,i)=pilot_t

ifft_data

end ifft_data = ifft(precoded_data,N_SC,1)

ifft_in_mat

other subcarriers will remain at ifft_in_mat = zeros(NUM_BS_ANT, N_SC, N_OFDM_SYMS/NUM_BS_ANT)

mod_fcn_16qam

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

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)))

MOD_ORDER

Parameters MOD_ORDER = 16

modvec_16qam

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

modvec_bpsk

end Modulate data modvec_bpsk = (1/sqrt(2)) .* [-1 1]

N_DATA_SYMS

N_DATA_SYMS = N_OFDM_SYMS * length(SC_IND_DATA)

N_OFDM_SYMS

N_OFDM_SYMS = (N_SYMS-NUM_UE)*NUM_UE

N_SC

N_SC = 2048

N_SYMS

N_SYMS = 70

noise

noise = (randn(N_SC,NUM_UE, NUM_BS_ANT) + 1i*randn(N_SC, NUM_UE, NUM_BS_ANT))/sqrt(2)/100

NUM_BS_ANT

NUM_BS_ANT = 8

NUM_UE

Reshape the symbol vector to a matrix with one column per OFDM symbol N_OFDM_SYMS NUM_UE = 8

OFDM_START_OFFSET

OFDM_START_OFFSET = 424

pilot_all_ue

end pilot_all_ue = reshape(pilot_all_ue, N_SC,1,NUM_UE)

pilot_est

pilot_est = zeros(N_SC,NUM_UE,NUM_BS_ANT)

pilot_f

pilot_f = randi(3,N_SC,1)-2

pilot_t

pilot_t = ifft(pilot_f, N_SC)

precoded_data

precoded_data = zeros(N_SC,NUM_BS_ANT,N_SYMS-NUM_UE)

precoder_all

precoder_all = zeros(length(SC_IND_DATA),NUM_BS_ANT,NUM_UE)

precoder_from_file

Precoder calculation and precoding precoder_from_file = zeros(N_SC,NUM_BS_ANT,NUM_UE)

return

return

rx_data

rx_data = arrayfun(demod_fcn_qpsk, rx_syms_mat(:))

rx_data_fft

rx_data_fft = fft(rx_mat_data,N_SC,1)

rx_data_from_file

rx_data_from_file = fread(fileID,[1,N_SC*N_SYMS*NUM_BS_ANT*2],'float')

rx_data_from_file_float

rx_data_from_file_float = rx_data_from_file(1:2:end)+1j*rx_data_from_file(2:2:end)

rx_mat

rx_mat = tx_mat*H

rx_mat_all

rx_mat_all = zeros(N_SC,N_SYMS,NUM_BS_ANT)

rx_mat_all_f

rx_mat_all_f = zeros(N_SC,N_SYMS,NUM_BS_ANT)

rx_mat_data

rx_mat_data = rx_mat_all(:,:,NUM_UE+1:end)

rx_pilot_from_file

rx_pilot_from_file = rx_data_from_file_float(:,1:8,:)

rx_syms

rx_syms = precoder * rx_data_fft

rx_syms_mat

rx_syms_mat = zeros(length(SC_IND_DATA),N_SYMS-NUM_UE,NUM_UE)

rx_vec

rx_vec = reshape(rx_mat_all, 1, numel(rx_mat_all))

rx_vec_float

rx_vec_float = zeros(1,size(rx_vec,2)*2)

SC_IND_DATA

SC_IND_DATA = 425:1624

size

Reshape to a vector size

tx_data

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

tx_data_dl

tx_data_dl = reshape(tx_syms,length(SC_IND_DATA),N_SYMS-NUM_UE, NUM_UE)

tx_data_dl_raw

tx_data_dl_raw = reshape(tx_data,length(SC_IND_DATA),N_SYMS-NUM_UE, NUM_UE)

tx_data_for_saving

tx_data_for_saving = reshape(tx_data, length(SC_IND_DATA), N_OFDM_SYMS/NUM_UE, NUM_UE)

tx_data_mat

tx_data_mat = reshape(tx_data,length(SC_IND_DATA),N_SYMS-NUM_UE,NUM_UE)

tx_mat

tx_mat = reshape(tx_mat_all,N_SC*N_SYMS,NUM_UE)

tx_mat_all

tx_mat_all = cat(2,pilot_all_ue,tx_payload_mat)

tx_mat_all_f

tx_mat_all_f = fft(tx_mat_all,N_SC,1)

tx_payload_mat

tx_payload_mat = ifft(ifft_in_mat, N_SC, 1)

tx_syms

case QPSK tx_syms = arrayfun(mod_fcn_bpsk, tx_data)

ue_rx_data

end ue_rx_data = arrayfun(demod_fcn_qpsk, dl_rx_data_fft(:))

values

Insert the data and pilot values