//通過18B20檢測的數字溫度可在電腦上顯示當前溫度值
#include <reg52.h>
#define uchar unsigned char
#define uint unsigned int
sbit DS=P2^2 //define interface
uint temp // variable of temperature
uchar flag1 // sign of the result positive or negative
sbit dula=P2^6
sbit wela=P2^7
復接入,B/W雙用戶使用直接擴頻序列
% >>>multiple access b/w 2 users using DS CDMA
% >>>format is : cdmamodem(user1,user2,snr_in_dbs)
% >>>user1 and user2 are vectors and they should be of equal length
% >>>e.g. user1=[1 0 1 0 1 0 1] , user2=[1 1 0 0 0 1 1],snr_in_dbs=-50
% >>>or snr_in_dbs=50 just any number wud do
% Waqas Mansoor
% NUST , Pakistan
SPREAD SPECTRUM MODULATION TECHNIQUES
-spread spectrum - those modulation methoDS that are producing a signal whose
spectrum is more wider than of the data signal, the occupied frequency band being
independent by the signal of data band.
-The signals with spread spectrum of direct sequence type BPSK (BPSK-DS-SS)
-The signals with spread spectrum of direct sequence type QPSK – DS–SS
- Frequency hopping spread spectrum signals (FH-SS)