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Technical Overview. This presentation is provided by the HomeRF Working Group. Direct questions or requests for softcopy to: Info@homerf.org, 503-291-2563 Or contact HomeRF Communications Chairman, Wayne Caswell (wayne.caswell@icm.siemens.com, 512-335-6073). Technical Overview Topics.
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Technical Overview Property of the HomeRF Working Group This presentation is provided by the HomeRF Working Group. Direct questions or requests for softcopy to: Info@homerf.org, 503-291-2563 Or contact HomeRF Communications Chairman, Wayne Caswell (wayne.caswell@icm.siemens.com, 512-335-6073)
Technical Overview Topics • Toll-quality Voice & Streaming Media • Data Throughput, Range & Attenuation • Security & Interference Immunity • Power Consumption & Form Factor • Cost Property of the HomeRF Working Group
Broadband Internet Laptop (A-node) asynchronous Wired network Internet Appliance (SA-node) Control Point (CP Class 1) Audio Headset (S-node) streaming Cordless Handset (I-node) isochronous HomeRF Node Types Property of the HomeRF Working Group
HomeRF Specification uses, references, or “maps into” existing network layers. { HomeRF Specification modifies existing technology OSI 7-Layer Network Stack Model 7. Application 6. Presentation Property of the HomeRF Working Group 5. Session 4. Transport 3. Network 2. Data Link (MAC) 1. Physical (PHY)
Existing Upper Layers UDP TCP DECT IP HomeRF MAC Layer Priority CSMA TDMA CSMA/CA HomeRF PHY Layer “Ethernet” Data Path Toll-Quality Voice Path Streaming Media Path Network Layer View Property of the HomeRF Working Group
MAC Layer Reserved time TDMA Contention-based “Wireless Ethernet” Plus priority access and time reservation Plus re-transmission option Beacon HomeRF Frame HomeRF Specification Basics PHY Layer 2.4 GHz FH Constant envelope FSK modulation Conventional synthesizer BACKUP Property of the HomeRF Working Group 0.8, 1.6, 5, 10 Mbps data rates
Re-Transmit Voice Calls Hop 2 1 Priority Streams Within data networking time, streaming media sessions get priority access If voice packets fail, they can be re-transmitted at the start of the next frequency Reserved time period based on number of active voice calls MAC Layer Basics Bulk of time is allocated to data networking time Property of the HomeRF Working Group Data Networking
10 ms 20 ms 10 ms 20 ms B B B B Hop Hop Hop Hop fN Data#1 Ack#1 Data#2 Ack#2 Data#3 Ack#3 Hop All asynchronous traffic fN+1 Data#4 Ack#4 Data#5 Dn#1 Up#1 Ack#5 Dn#1 Up#1 fN+2 Beacon is added for Isochronous traffic and frame length is reduced to 10ms fN+3 Ack#6 Data#6 Dn#3 Dn#1 Data#7 Up#3 Up#1 Ack#7 Dn#3 Up#3 fN+4 Second call is added First call ends. Frame reordered. fN+5 Data#8 Ack#8 Data#9 Ack#9 Data#10 Ack#10 Hop Superframes and Subframes Property of the HomeRF Working Group
Bandwidth Requirements Property of the HomeRF Working Group
Technical Overview Topics • Toll-quality Voice & Streaming Media • Data Throughput, Range & Attenuation • Security & Interference Immunity • Power Consumption & Form Factor • Cost Property of the HomeRF Working Group
75 1 MHz channels for 1.6 Mbps data and all voice communications 5 MHz Superchannel 15 5 MHz channels for 5 and 10 Mbps data modes 1 MHz Base Channel Wideband Frequency Hopping HomeRF improves performance of 802.11 FH Enabled by FCC rule change in August 2000, ETSI rule change in December 2001 Property of the HomeRF Working Group f
0.8-1.6 Mbps 5 Mbps Throughput ~5 Mbps ~2.5 Mbps ~0.4-0.8 Mbps RANGE: Signal Strength Diminishes with Distance Property of the HomeRF Working Group Advertised Range 150’ Advertised Data Rate: 10 Mbps 0’ 85’ 130’ 150’
6 5 MPEG2 Video 4 Nominal throughput (Mbps) 3 2 Broadband/ MPG 4 Video 1 Dial-up / MP3 Audio 0 10' 20' 30' 40' 50' 60' 70' 80' 90' 100' 110' 120' 130' 140' 150' Source: Practical and Theoretical Calculations Performance over Distance HomeRF provides real-time media streaming to more nodes over a greater distance. Property of the HomeRF Working Group
The Higher the Frequency, the more signal loss.5 GHz is worse than 2.4 GHz. Attenuation: Signal Strength Diminishes through Materials Wood and plaster Walls or Floors are OK. Even Brick. Property of the HomeRF Working Group BUILDING WALL Metal and thick rock block the RF signals.
Multi-path in Homes:More Absorption, Less Reflection Property of the HomeRF Working Group Signals can arrive at different times and cancel each other out.
Technical Overview Topics • Toll-quality Voice & Streaming Media • Data Throughput, Range & Attenuation • Security & Interference Immunity • Power Consumption & Form Factor • Cost Property of the HomeRF Working Group
is Secure and Reliable • Frequency Hopping Spread Spectrum • Invented for the US Military to avoid jamming,denial of service, and eavesdropping • Performance with Interference • Microwave ovens, cordless phones,baby monitors, video senders, neighbors • High Density Apartments • Security Layers • Application Layer Security Option • 128-bit Encryption Option • Standardized Teach/Learn • 24-bit Network ID • Random Frequency Hopping • Spread-Spectrum • Digital Property of the HomeRF Working Group
Access from car or hilltop ??? is Secure and Reliable Typical Wi-Fi configuration with 3 non-overlapping channels. BUILDING WALL BEWARE: RF signals can penetrate walls
Interference:HomeRF hops around it FHSS DSSS 2.5 GHz Property of the HomeRF Working Group Frequency 2.4 GHz Time Time IEEE 802.11b waits for Interference to go away
Next hop clear Next hop clear Next hop clear Next hop clear Next hop clear Power Spectral Density Used ISM band (75 MHz) Frequency Average Power Spectrum (10 to 30 MHz) Active Interference Avoidance Spectral / Temporal Characteristics of Microwave Ovens Property of the HomeRF Working Group
10 ms Dn5 Up5 Active calls Active data traffic fN Hop Beacon Data 1 Ak1 Interference 1 contacts fN Data packet succeeds on retry Control point allocates retry of up/down 2 Normal calls continue fN+1 Hop Beacon Data 2 Ak2 Dn2 Up2 Dn5 Up5 Dn2 Up2 Active Interference Avoidance Data 2 Dn2 Up2 Property of the HomeRF Working Group Latency is bounded to 10 ms even in the presence of interference
IEEE 802.11b Signal Strength 802.11b – DSSS using channel 3 (static frequency) Frequency over Time 2.50 GHz Property of the HomeRF Working Group 2.5 GHz 2.4 2.45 GHz 2.40 GHz 0 500 s 250 Source: Celerity Digital Broadband Test
Signal Strength Frequency over Time 2.50 GHz 2.5 GHz 2.4 2.45 GHz 2.40 GHz 0 500 s 250 Bluetooth™ Bluetooth Headset signal 31.25 µs between pulse pairs 125 µs between pulse sets Property of the HomeRF Working Group Source: Celerity Digital Broadband Test
Frequency over Time 2.50 GHz 2.45 GHz 2.40 GHz 0 500 s 250 2.4 GHz Cordless Phone Signal Strength Multiple Channel Cordless Telephone Transmit Receive on separate channels Channel selection is arbitrary Property of the HomeRF Working Group 2.5 GHz 2.4 Source: Celerity Digital Broadband Test
Signal Strength Frequency over Time 2.50 GHz 2.5 GHz 2.4 2.45 GHz 2.40 GHz 0 500 s 250 Coexistence within ISM band WLAN 802.11b Bluetooth™ Cordless Telephone Property of the HomeRF Working Group 802.11b politely waits for interference to go away – potentially a very long time with cordless phones. Bluetooth interference, at 1600 hops/sec can also be severe. Source: Celerity Digital Broadband Test
Technical Overview Topics • Toll-quality Voice & Streaming Media • Data Throughput, Range & Attenuation • Security & Interference Immunity • Power Consumption & Form Factor • Cost Property of the HomeRF Working Group
Simple Design: enables small form factor for embedded apps • Smallest WLAN form factor • 1.6 Mbps and full home coverage • < 10mW standby power draw • Full TCP/IP connectivity • Ideal for handheld Internet appliances, personal imaging and audio devices Update for 2.0? Property of the HomeRF Working Group • Specifications: • Physical • Type II size, < 20 grams • 0 – 40 degree C operation • CE, EMC-EEC 89/336 Compliant • Electrical • 3.3 V, 120mA Rc; 250mA Tx modes • 3mA standby mode
Hand Held Trends • Larger, higher resolution Displays with more Colors • More Performance, Less Cost • e.g. Video streaming • Better Text rendering • Wireless (WAN, WLAN, PAN) • PDA becomes Phone, MP3… • Phone becomes PDA, MP3… • Digital Imaging • PocketPC gains some ground • Palm still has >70% share Property of the HomeRF Working Group With Microsoft ClearType, palm-sized devices can act as eBooks.
Technical Overview Topics • Toll-quality Voice & Streaming Media • Data Throughput, Range & Attenuation • Security & Interference Immunity • Power Consumption & Form Factor • Cost Property of the HomeRF Working Group
Cost Roadmap parallels DECT • DECT is a leading indicator for HomeRF • 6 generations of architecture evolution • HomeRF comes in well down the learning curve • Complexity is similar • HomeRF Baseband ROM/Flash about 2X DECT • Radio will reuse Bluetooth/DECT Low-IF IP • HomeRF BOM cost will approach DECT at same volumes • Basic HomeRF functionality (voice + 10Mbps) • Additional SW & HW depends on product features Property of the HomeRF Working Group
Cost Synergies • Easy compatibility with OpenAir • HomeRF and OpenAir share a common PHY (dual MAC client devices available now) • OpenAir has over 1M devices from over 20 different vendors already deployed in the field • Multi-mode client devices with Bluetooth • HomeRF and Bluetooth have similar PHY(multi-MAC client devices, such as a PCMCIA or Compact Flash card, are feasible and expected in 2002) Property of the HomeRF Working Group
Cost Synergies, cont. • Multi-mode / Multi-band clients • PCS / GSM phones • 802.11b / .11g (DSSS / OFDM) • 802.11b / Bluetooth (DSSS / FHSS) • 802.11b / .11a (2.4 / 5 GHz) • WLAN / WAN (for mobile workers) • Easy to include support for HomeRF • Adds much needed Flexibility • Automatically sense and adapt to networks Property of the HomeRF Working Group
Simple Design: enables Inexpensive 2-chip solutions Top Side RFIC Property of the HomeRF Working Group Integrated Baseband Bottom Side Flash
Summary • Ideal for the Broadband (voice, data, entertainment) • Blends several technologies to enable Digital Convergence • Broadband data at Ethernet speeds “plus” toll-quality voice and streaming media • Designed and optimized for Households & SOHO: • Simplicity, Security/Privacy, Interference, Cost, Applications • Smooth roadmap to 20 Mb/s and beyond • Multi-band support for 2.4 GHz and 5 GHz (802.11a) • More information at www.HomeRF.org • Learning Center for W.Papers, Presentations, etc. Property of the HomeRF Working Group
Wireless Choicesfor the Broadband Internet home ATTRIBUTE HomeRF Bluetooth 802.11b Cost ~ Security ~ X Interference Immunity X ~ Toll-Quality Voice Support ~ X Property of the HomeRF Working Group Streaming Media Support ~ X ~ Data Throughput X Range X Power Consumption X ~ Form Factor X ~ Network Topology ~ ~ Roaming Outside the Home ~ ~ ~ ~- Adequate X- Disadvantage - Advantage Legend: