' ********************************************************

' *  PROGRAM TO ILLUSTRATE THE EFFECT OF NOISE AVERAGING *

' *   IT RETRIEVES A SIGNAL BURIED (20DB DOWN) IN NOISE  *

' ********************************************************

SCREEN 9, 1: COLOR 15, 1: CLS : PI = 3.141592653589793#

PI2 = 2 * PI: K1 = PI2 / 200: X0 = 100: YM = 170

DIM D1(4, 19), D2(2, 400), XD%(400)

FOR I = 1 TO 18

FOR J = 1 TO 4

READ A

D1(J, I) = A

NEXT J

NEXT I

INPUT "INPUT A/D DYNAMIC RANGE AS 2^N.  N ="; N

DY = 100 / (2 ^ N)

FOR M = 1 TO 60000

I2 = 0

FOR J = 1 TO 18

FOR I = I2 TO D1(1, J)

XD%(I) = INT(I - D1(2, J))

D2(1, I) = D2(1, I) + DY * INT((D1(3, J) + 141 * (RND(1) - .5)) / DY)

D2(2, I) = D2(2, I) + DY * INT((D1(4, J) + 141 * (RND(1) - .5)) / DY)

NEXT I

I2 = D1(1, J) + 1

NEXT J

CLS

FOR I = 1 TO 400

LINE (X0 + XD%(I), YM + D2(1, I) / M)-(X0 + XD%(I), YM + D2(2, I) / M)

NEXT I

LOCATE 1, 50: PRINT M

IF M > 1000 THEN 1200

FOR L = M TO 1000

FOR KTIME = 1 TO 30: NEXT KTIME

NEXT L

1200 NEXT M

1333 A$ = INKEY$: IF A$ <> "G" THEN 1333

STOP



DATA 100,0,0,0,103,0,-6,6,114,0,-1,1,118,0,-6,6,148,0,0,0,152,0,-6,6

DATA 162,0,-6,-5,172,10,-1,1,182,20,4,6,213,30,0,0,216,30,-6,6,227,30,4,6

DATA 267,40,0,0,271,40,-6,6,277,40,-6,-5,283,46,-1,1,287,46,-6,1,400,46,0,0



