1. Spread Spectrum Techniques found in LPRF & GNSS Bluetooth – Dynamic Frequency Hopping – to avoid RF collisions ZigBee – Transformation of bit patterns from 4 to 32 bits using Modulo-2 Spreading Code – to provide error detection and correction GNSS – Use of modulo-2 Spreading Codes to achieve Code Division Multiple Access with a code correlator

2. Spread Spectrum Techniques found in LPRF & GNSS Bluetooth – Dynamic Frequency Hopping – to avoid RF collisions

3. Direct Sequence Spread Spectrum ZigBee – Transformation of bit patterns from 4 to 32 bits using Modulo-2 Spreading Code – to provide error detection and correction

4. CODE DIVISION MULTIPLE ACCESS GNSS – Use of modulo-2 Spreading Codes to achieve Code Division Multiple Access with a code correlator BINARY GNSS CODE 0011101001010.... PSEUDO RANDOM NOISE (PRN) 1023 BITS + Correlation

5. Infra Red Data Association IRDA UART like IR based protocol – typically 115200 BPS Other speeds 2400, 9600, 19200, 38400, 57600, 115200, 576000, 1152000, and 4000000 bits per second Sub Carrier x16 – min bit is 3 clocks wide IR -Comm – simple serial comms OBEX – HTTP like Object Exchange Protocol

6. Infra Red Data Association IRDA Image taken from texas Instruments TIR1000, TIR1000I STANDALONE IrDA  ENCODER AND DECODER

8. Radio Frequency ID Passive uses electo-magnetic coupling Active has internal power source Range of frequencies 125 - 134 kHz 13.56 MHz UHF (400MHx and 860 to 960 MHz) 2.45 GHz 5.8 GHz