‘RF-Lite’a solution for Low Data Rate Application: ‘RF-Lite’ a solution for Low Data Rate Application Benno Ritter Philips Semiconductors


Contents: Contents Introduction Target Markets & Application Scenarios PURL Protocol Air Interface Physical Layer Application Scenarios System Realisation Demonstration


Preface: Preface Based on work performed in RF-Lite (Firefly) committee (http://12.5.139.199) 20 companies are members and growing MRD V0.91 TRD V0.9 Current revision of the spec V0.8 Spec V1.0 to be finalized in Q2/01


Introduction: Introduction Success Factors Target Markets Applications & Environment Market Sizes


Success Factors: Success Factors Low cost Data type support Unlicensed band Unrestricted geographical use Global implementation Governmental regulations


Low Cost: Low Cost The added cost of the RF communication capability must be at or below existing consumer price points for end user solutions currently servicing these markets. (interactive wireless joystick would be expected to cost the same as an existing IR or wired joystick) In Home Automation systems, the added cost needs to be comparable to the most efficient cost of installing a wire to a specific device.


Data Type Requirements: Data Type Requirements An aggregate data link service of at least 115 kbps is needed to support the following data types: One asynchronous data link at a rate up to 115.2 kbps (RS232) Voice recognition at a peak aggregate rate of up to 64 kbps Text-to-speech (TTS) Critical latency applications, such as, interactive gaming USB packets excluding isochronous transfer types Any combination of the above data types subject to aggregate capacity limitations


Unlicensed Band & Unrestricted Geographical Use: Unlicensed Band & Unrestricted Geographical Use Unlicensed Band The user is not required to apply for any licenses to operate the product implementing this specification. Unrestricted Geographical Use Within a geographical (or political) region, there should not be any restrictions on its use. Users would expect to be able to purchase the device implementing this RF technology at one part of the geographic region and use it in another part. The geographic region can be as localized as a country (e.g. USA or Japan) or a geo-political area such as European Union where the standards are uniform.


Global Implementation & Governmental Regulations: Global Implementation & Governmental Regulations Global Implementation A desirable consideration is to have one specification (and implementation) that can be sold and used internationally with minimum product variation. Governmental Regulations The specification will need to comply with the appropriate regulations in force at the time for the geographical or political region (includes regulations relating to safety, energy, radiation, etc.)


Target Markets: Consumer Electronics Low-End Radio Devices PC Peripherals Home Automation Toys & Games Personal Healthcare · TV · VCR · DVD · CD · Remote · … · Mouse · Keyboard · Joystick · Gamepad · … · Security · HVAC · Lighting · Closures · … · PETs · Gameboys · Educational · … · Monitors · Diagnostics · Sensors · … Target Markets


Applications & Environment: Applications & Environment Human Input Devices (HID) Home Automation & Control Home Security & Interactive Toys


Human Input Devices (HID) 1: Human Input Devices (HID) 1 Keyboard Communication is typically uni-directional Expected throughput: 1.0 kbps Expected response time: < 50 msec. Expected Battery Life: 6 months min. with typical use (defined as 10 keystrokes/second for 3 hours/day) Mouse / Pointing Device Communication is typically uni-directional Expected throughput: 3.0 kbps Expected response time: < 25 msec. Expected Battery Life: 6 months min. with typical use (defined as updating the screen 5 times/second for 3 hours/day) Remote Controls (controls for audio & video equipment) Communication is uni- and/or bi-directional Expected throughput: 3.0 kbps Expected response time: < 25 msec. Expected Battery Life: 6 months min. with typical use (defined as updating the screen 5 times/second for 3 hours/day)


Human Input Devices (HID) 2: Human Input Devices (HID) 2 Gaming Device Double Joystick Communication is typically bi-directional for feedback controllers Expected throughput: 6.0 kbps Expected response time: < 16.7 msec. Expected Battery Life: 6 months min. with typical use (defined as updating the screen 5 times/second for 3 hours/day) Game Pad for DirectX Communication is typically bi-directional for feedback controllers Expected throughput: 9.0 kbps Expected response time: < 16.7 msec. Expected Battery Life: 6 months min. with typical use (defined as updating the screen 5 times/second for 3 hours/day)


Home Automation & Control: Home Automation & Control Automated lighting, temperature control, maintenance, and amenities Interaction with a controller for updates and supervisory functions Automation Devices Communication is uni- and/or bi-directional Expected data rates: 2 years operating on 2AA batteries Very low power consumption High density of units, up to 128 Control Devices Communication is uni- and/or bi-directional Expected data rates from 2 years operating on 2AA batteries Very low power consumption Medium density of units, up to 64


Home Security & Interactive Toys: Home Security & Interactive Toys Home Security Communication is uni- and/or bi-directional Expected data rates: 2 years operating on 2AA batteries Very low power consumption High density of units, up to 128 Interactive Toys In-room interaction with TV or PC program Home+yard coverage for mobile robots and multi-user gaming Support for voice recognition and TTS desired Communication link must support bi-directional communication Some applications may need to support packetized audio at 32 kbps with latencies on the order of 100 msec. Expected bandwidth: 115.2 kbps Must support four (4) simultaneous links Use the “Alkaline Battery Model” – throw away after use Expected battery life: > 3 months with typical use (Low data rate toys) Expected battery life: > 30 days with typical use (Medium data rate toys) Typical use is defined as 4 hours/day


Estimated Market Size for Home Applications: Estimated Market Size for Home Applications Including White goods Home security HVAC PC peripherals Excluding Industrial control Medical equipment Remote controls Rough estimation based on forecast for goods only, wireless link penetration estimated So far no overall market numbers are existent Philips analysis based on reports from Gartner and Instat 1999


Market Drivers: Market Drivers Extremely low cost Ease of installation Reliable data transfer Short range operation Reasonable battery life


Philips Solution: Philips Solution Protocol specification (“PURL”) Software design and implementation Air interface design Baseband and radio IC implementation


PURLProtocol for Universal Radio Links: PURL Protocol for Universal Radio Links


Contents: Contents Lite Overview PURL Flavours Data Transfer Network Management


RF-Lite Overview: RF-Lite Overview


PURL Features: PURL Features Master/slave topology Automatic network configuration Dynamic slave device addressing Virtual peer-to-peer links (pairing) Full handshaking for packet transfers Power management features Up to 254 (+ master) network nodes


PURL Features Cont...: PURL Features Cont... CSMA-CA channel access mechanism 15ms frame structure TDMA slots can be allocated 12kbps & 115kbps (actual) data throughput Service discovery Low impact internet capability Extended sleep periods for slave devices (programmable through application SW)


PURL Flavors: PURL Flavors


PURL Slave Node: PURL Slave Node PURL On-air Protocol Stack PURL PHY Radio PURL Slave Node PURL API PURL MAC PD-SAP PM-SAP MD-SAP MM-SAP User Interface Slave APL PURL DLC


PURL Host Enabled Master Node: PURL Host Enabled Master Node PURL On-air Protocol Stack PURL PHY Radio PURL Master Node PURL API PURL MAC PURL DLC PD-SAP PM-SAP MD-SAP MM-SAP DD-SAP DM-SAP Host Transport Host Interface PHY Host Stack PURL Transport PURL Interface PHY Host Application Host User Interface Host Local User Interface Master APL PURL NWK


Data Transfer: Data Transfer


Frame Structure: Frame Structure Time, ms t + tf t Basic frame: Network beacon Contention period


Data Packet Structure: Data Packet Structure


Data Transfer Model: Data Transfer Model Master Slave Default control pipe Function pipes Control endpoint Function endpoints


Network Management: Network Management


Network Initiation: Network Initiation Master capable devices only Listens for network beacons Attempts to invoke network beacons Assumes unique network identifier Starts master operation


Network Topology: Network Topology Remote TV Curtains DVD Lamp Master node Slave node Communications flow


Air Interface Physical Layer: Air Interface Physical Layer


Frequency Bands: Frequency Bands 2.4GHz ISM band Channel spacing: 3MHz F = 2404 + 3k MHz with k = 0, 1, …, 25 Common band: USA, Europe including France and Spain 2.449MHz – 2.470MHZ k = 15, …, 22; equals 8 channels 915MHz ISM band USA only


Direct Sequence: Direct Sequence Spread spectrum regulations allow higher transmit power Longer range Transmit power: -4 to +20dBm Direct sequence Faster acquisition than frequency hopping Complexity in digital domain (cheaper)


Direct Sequence: Direct Sequence Spread using length 11 Barker sequence Optimal autocorrelation properties Short sequence gives fast acquisition Used in IEEE802.11 ‘1’ sent as: 10110111000 2.2Mchips/sec Processing gain of 10.4dB


Modulation: Modulation GFSK Constant envelope  (cheap) non-linear PA Spectral efficiency Modulation index; h = 0.5 Pre-modulation filter; BT = 0.5


Bit Rates: Bit Rates 200kbps (raw) 21.875kbps low bit rate option: Trade data rate for extra range via coding Over air bit rate remains 200kbps Hadamard Error Correction Coding achieves reliable link at low SNR Longer preamble and SOP reliable synchronisation at low SNR


Range Estimation: Range Estimation Using Firefly TRD/RSI propagation model Approx. x2


Air Interface Summary: Air Interface Summary Direct Sequence 2.2Mchips/sec 2.4GHz band (and 915MHz) 200kbps -4 to +20dBm GFSK, h = 0.5, BT = 0.5 Low data rate option: 21.875kbps


Application Scenariosand System Realisation: Application Scenarios and System Realisation


Applications :- Slave Device: Applications :- Slave Device Light Switch Thermostat Accessory Control Security Sensor Computer Keyboard


RF-Lite Block Diagram: RF-Lite Block Diagram RF IC Control Transmit Data Receive Data BASEBAND Application


Development Platform: Development Platform


RF-Lite ProtocolDemonstration: RF-Lite Protocol Demonstration


Current Demonstration: Current Demonstration


Thanks: Thanks


Target Applications 1: Target Applications 1 Desktop PCs and Home Entertainment Systems (Home Theatre TV) Computer peripherals; HID devices Video conference equipment Remote control Video gaming equipment Multi-player PC & video games Playing a PC DVD game in front of a TV monitor Remote controls for audio and video equipment PC Enhanced & stand alone toys In-room coverage Home+yard coverage


Target Applications 2: Target Applications 2 Home appliances and general consumer electronic devices Existing home security systems, electrical & heating systems Wireless door and opening monitoring, system control Glass breakage monitoring (sensors) Wireless Keypads Child Monitor Smoke and flame detectors Fire Pull stations Personal transponders Lighting and remote control of appliances in the home; Blinds Shades Fireplaces Pool/Spa equipment Garage door openers Voice Control Home Comfort Control New device categories that have not yet been developed, such as news tablets, and keyboards with built-in displays


Modulation: Modulation Transmitted spectrum:


Simulated Performance: Simulated Performance


Link Budget: Link Budget Propagation models: Firefly-TRD/RSI Attenuation = 50.2 + 28log(d) dB IEEE 802.15 Attenuation = 40.0 + 20log(d) dB (d<8m) = 58.5 + 33log(d/8) dB (d8m)


Range Estimation: Range Estimation