Low Power Radio Frequency LPRF Industrial Scientific Medical

Low Power Radio Frequency LPRF Industrial Scientific Medical ISM 433 MHz 688 MHz 868 MHz 2. 4 GHz 5. 8 GHz 915 MHz in US Licence Free – Short Range – Open Standards (i. e. no licenced protocols)

LICENCED PROTOCOLS IN THE LPRF BANDS Zig. Bee Blue. Tooth Z Wave ANT++ Wi. Fi And so on. . . . 868 & 2. 4 Smart Meters, Health 2. 4 Personal Devices 868 Home Automation 2. 4 Fitness Market 2. 4 Computers

BLUETOOTH – 2. 4 GHz offering point to point communciations for commercial products Hands Free Kit IT peripherals Data Streams OEM Applications Home entertainment

Serial USB or Analogue (PCM) RF Data Link Host computer or device HCI

DEVICE 1 DISCOVERABLE DEVICE 2 DISCOVERY Sees Board Address Friendly Name Device Type REQUEST TO PAIR OPTIONAL ENCRYPTION AND PIN NUMBER REQUEST ISSUE PIN NUMBER CREATES LINK KEY PAIRED -------------------------------- CONNECTS

Blue Tooth Board Address 48 bits (12 HEX) Friendly Name 18 Characters Device Type 24 bits (6 HEX)

Zig. Bee – creates ad-hoc Mesh Networks known as Personal Area Networks PAN 2. 4 MHz, 868 MHz (EU), 915 MHz (USA) A PAN Id has 24 -bits Each Node has 8 -bits Co-Ordinator Finds free channel and assigns a PAN ID. It also acts as a Router Nodes request to join – Must be running the correct Zig. Bee Profile and Application Profile – they are the allowed to join and are assigned a Node Id. If we are using a Trust Centre then there is a deeper level of security that must be followed e. g. Smart Energy Profile. Nodes can act as routers or end-points – thus we create a Tree Network Co-Ordinator (tree) 1 t 1. 1 1. 2 2 1. 3 2. 1 2. 2 3 2. 3 3. 1 3. 2

Co-Ordinator (with routing tables) 1 t 1. 1 1. 2 2 1. 3 2. 1 2. 2 3 2. 3 3. 1 A true Mesh Network, but with higher processing overhead 3. 2

Z-WAVE 868 & 915 32 bit network or home ID 8 bit node ID Uses a mesh network with a master and optional secondary controllers MAX 232 nodes Each node senses 6 nearest devices and informs controller No security

Z-WAVE IS WIDELY USED FOR HOME AUTOMATION Inter-operability

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