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- added finding peak width

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git-svn-id: http://moon:8086/svn/software/trunk/projects/GnuRadio@445 b431acfa-c32f-4a4a-93f1-934dc6c82436
This commit is contained in:
jens
2019-05-23 16:41:45 +00:00
parent 0b816e8113
commit 8cf7726af8
1 changed files with 65 additions and 31 deletions
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matlab/peak_detect.m
+65 -31
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@@ -38,10 +38,12 @@ pa = 0.3;
d_max = 30;
am = 0.04;
as = 0.9;
Ad = 15;
as = 0.2;
Ad = 20;
Cm = 0;
pbh = 5;
pb_min = 5
pb_max = 37
s = zeros(1, Nh);
a = zeros(1, Nh);
@@ -83,11 +85,12 @@ for k=1:numFrames
% Init
if k == 1
Xm = Xm + mean(X);
Xs = Xs + mean(X);
endif
% Peak detection
Xs = (1-as)*Xs + as*X;
gate_peak = Xs > (Ad+Xm);
gate_peak = (Xs-Xm) >= Ad;
peak_count = gate_peak.*peak_count + gate_peak;
% Output
@@ -133,35 +136,73 @@ for k=1:numFrames
peak_boxes_rel = zeros(1, Nh);
peak_boxes_abs = zeros(1, Nh);
for x = peak_cand_sorted,
pbox_start = max(1, x-pbh);
pbox_end = min(Nh, x+pbh);
% Find intersection
box_height_rel = Xs(x) - Xm(x);
box_height_abs = X(x);
does_intersect = 0;
for n=pbox_start:pbox_end
if peak_boxes_rel(n) > box_height_rel
does_intersect = 1;
break
% Find peak widths
left = x;
right = x;
nom = X(x) - 10;
left_found = 0;
right_found = 0;
while(~(left_found & right_found))
% Determine peak width left from center (x)
if X(left) > nom
if left > 1
left = left - 1;
else
left_found = 1;
end
endfor
if does_intersect == 0
peak_boxes_rel(pbox_start:pbox_end) = box_height_rel * ones(1, pbox_end - pbox_start + 1);
peak_boxes_abs(pbox_start:pbox_end) = box_height_abs * ones(1, pbox_end - pbox_start + 1);
peak_final = [peak_final x];
else
left_found = 1;
endif
% Determine peak width right from center (x)
if X(right) > nom
if right < Nh
right = right + 1;
else
right_found = 1;
end
else
right_found = 1;
endif
pbh_left = x - left;
pbh_right = right - x;
% Take larger peak width
pbh = max(pbh_left, pbh_right);
% Ensure peak box is at least pb_min
pbh = max(pbh, pb_min);
end
% Use peak width for peak box
pbox_start = max(1, x-pbh);
pbox_end = min(Nh, x+pbh);
% Find intersection
box_height_rel = X(x) - Xm(x);
box_height_abs = X(x);
does_intersect = 0;
for n=pbox_start:pbox_end
if peak_boxes_rel(n) > box_height_rel
does_intersect = 1;
break
end
endfor
if does_intersect == 0
peak_boxes_rel(pbox_start:pbox_end) = box_height_rel * ones(1, pbox_end - pbox_start + 1);
peak_boxes_abs(pbox_start:pbox_end) = box_height_abs * ones(1, pbox_end - pbox_start + 1);
peak_final = [peak_final x];
end
endfor
% Update Xm at no-peak bins
gate_upd = peak_boxes_rel > 0;
Xm = (1-am)*Xm + am*X;
% Fill peak gaps with guessed values
last = Xm(1);
for n=2:Nh,
if gate_upd(n) == 0
last = 0.5*last + 0.5*Xm(n);
if (Xm(n) < (last+2)) or (peak_boxes_rel(n) == 0);
last = (1-am)*last + am*Xm(n);
else
Xm(n) = last;
end
@@ -175,15 +216,8 @@ for k=1:numFrames
subplot(2, 1, 1)
plot(1:Nh, X, peak_final, X(peak_final), 'ro', 1:Nh, peak_box_values, 'm-'); grid; axis([0, Nh, -60, 40]);
subplot(2, 1, 2)
plot(1:Nh, Xs, 1:Nh, Xm); grid; axis([0, Nh, -60, 40]);
plot(1:Nh, Xs-Xm, 1:Nh, Xm); grid; axis([0, Nh, -60, 40]);
pause(1/30);
end
function s = matchedFilter(N, B)
n2 = (N-1)/2
n = (0:N-1)-n2
s = sinc(n/B)
endfunction
endfunction