Tennessee Tech UNIVERSITY Wireless Sensor System Design

Tennessee Tech UNIVERSITY Wireless Sensor System Design § A Joint Course of the University of South Florida and Tennessee Technological University Spring 2002 § Lecture 7 - Wireless Communication Systems § §

Weekly Lecture Topics Ñ Course Introduction Analog and Digital Modulation Methods (1/11) Fundamentals of Antennas and Propagation (1/18) Signal Processing Techniques (1/25) Microwave Systems: Communications Hardware, Noise, Linearity (2/1) System Test, Evaluation and Documentation / Effective Presentation Styles (2/8) Preliminary Design Review (student presentations*) (2/15) Microwave Sensor Technology (2/22) @ TTU § Modern Wireless Communication Systems (3/1) § TBD (3/8) Critical Design Review (student presentations*) (3/22) Microelectromechanical Systems (MEMS) Sensors (4/5) Wireless Sensor System Research (Paul Flikkema from NAU) from USF (4/12) Review / Course Wrap-up (4/19) Ñ Ñ Ñ Ñ § § * On-site internal reviews/preparation will precede inter-university presentations. USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Outline § Why wireless communication systems? § Four examples of wireless telecommunications systems § Design criteria as related to class project USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Wireless Communication Systems: WHY? § Transmission media § Wired - wire/fiber § Wireless - air § Quick installation of infrastructure § e. g. , straight to mobile in developing countries § User mobility § Shared access § TDMA § FDMA or combinations of § CDMA USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Example 1: Satellite Broadcasting Shaped pattern HUB USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS 22, 400 miles Tennessee Tech UNIVERSITY

Example 1: Market for Direc. TV § § § Terrestrial Broadcast TV § An analog system of limited range § Each channel occupies 6 MHz § VHF (CH 2 -13): 54 -216 MHz § UHF (CH 14 -83): 470 -890 MHz Regular Cable: same technology, just over wire Need for an alternative? § Cable not available everywhere § Cable had a “monopoly” § Analog system had a limited number of channel (82) USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Example 1: Technology § High-power direct broadcast satellite operating at Kuband (14/12 GHz) § All signals uplinked from single location § Service (downlink) to any CONUS location § Analog audio and video signals are § § § Digitized Compressed (MPEG-2, 8: 1) Encoded Multiplexed “Inexpensive” receivers USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Example 1: Receiver Technology § § Ku-band enables small receiving dish § directivity ~1/ Digital signal provides § CD quality sound § “Better” picture § Additional services § More channels: “ 500!” USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Example 1: Summary § § § Promise of high-quality, nation-wide service obtained Advantages § Easy to add new customers (database change) Disadvantages § Large customer and venture investment up-front § No standard among providers § Compression can break down § Cable is catching up (Tom Switched!) § Limited bandwidth, HDTV? § Rainfade (FL - high gain slope and rain rates) USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Example 1: Gain Slope & Pointing HUB OK USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS NOT OK Tennessee Tech UNIVERSITY

Example 2: Cell phones § § § Spatial Isolation w/ channel groups § Time (TDMA) 4 § Freq (FDMA) 5 § Code (CDMA) 3 Cell size 1 § Capacity 6 2 § Power 7 § size 0 : wired Reuse: e. g. , N=7 makes a cluster 3 § N - better isolation § N - better reuse § more clusters more reuse more capacity USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS 3 2 4 1 Tennessee Tech UNIVERSITY

Example 2: Changing Cells § § § Handoff Uses different set of channels channel groups can be reused when cells are “far” apart § reusing channel increases system capacity 3 4 5 3 2 1 6 2 4 7 USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS 3 1 Tennessee Tech UNIVERSITY

Nice Geometry is not Reality! Source: University of Kansas' Information & Telecommunications Technology Center and Kansas Applied Remote Sensing Program USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Example 3: WLAN: Bluetooth § Cellular idea implemented in extremely small scale § 10 cm - 100 m (10 m nominal) § 2. 4 GHz band § Up to 79 channels (@ 220 k. Hz) separated at 1 MHz intervals § Low power (RF and DC) § FHSS USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Thanks Asa Tennessee Tech UNIVERSITY

Example 3: Bluetooth Applications § § Internet Bridge § Laptop § Cell Phone § LAN Peripheral Interface § PC § PDA § Printer § Keyboard § Mouse USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Aware devices! Tennessee Tech UNIVERSITY

Example 4: Wireless Sensor Systems § § § Wireless Sensing: § Non-invasive, remote sensing Wireless Link: § Ease of installation - Low impact § Wide coverage region § Unique characteristic: Low bandwidth requirements In this class we’ve discussed both wireless sensing and communications USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Example 4: Wireless Sensing § Active § Radar and Lidar § § Speed and position PROXIMITY § Passive § Radiometry and IR Imaging § § Composition Thermal profile: measure emissivity for different wavelengths USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Example 4: Wireless Link USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Example 4 - Bottom Line § Wireless sensors § In situ measurement § Non-invasive § Ease of placement § Mobility § Ubiquitous USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

So what is next: Hype or Buzz? § Three years ago: § Satellite based global cellular systems § Two years ago: § Satellite based broadband systems § Last few years: § 3 G USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

So what is next – the Reality § Satellite based global cellular systems § Iridium and Globalstar (bankrupt), ICO (DNS) § Satellite based broadband systems § Teledesic (designed and redesigned: 800 to 30 satellites), Spaceway, etc. still not launched § 3 G: Promise of mobile internet and telematics § Is there the bandwidth? Is there a standard? USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

So what is next – the Reality § Satellite based global cellular systems § Iridium and Globalstar (bankrupt), ICO (DNS) § Satellite based broadband systems § Teledesic (designed and redesigned: 800 to 30 satellites), Spaceway, etc. still not launched § 3 G: Promise of mobile internet and telematics § Is there the bandwidth? Is there a standard? Is there a demand? USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

So what is happening? § WLAN § 802. 11 b (11 Mbps) and Bluetooth (720 kbps) § Satellite based systems § XM and Sirius digital radio § On. Star telematics § In building wireless § Your mobile phone becomes part of the company exchange inbuilding § Maintains regular mobile functions off-campus § SEEMS THE FIELD IS MARKET DRIVEN! USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Comm Systems: Pertinent Design Criteria § The bottom line: What signal quality do you need? Quantified by Signal-to-Noise Ratio (SNR) § § Optimize signal power (S) and bandwidth (B) given noise constraints Drives the design of: § Antennas § Data Rates § Amplifiers § Filters § Range § Processing § Everything USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Wireless Communications Summary § § § Wireless advantages: § Mobility and potentially reduced infrastructure costs Wireless disadvantages: § Limited bandwidth and more expensive user devices Control Power and Bandwidth to achieve desired § SNR ratio (signal quality) § Range § Data rates USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Design Criteria as Related to Project § § Range § frequency of operation, amplifier gains, antennas, etc. Beamwidth § Directivity vs. beamwidth Bandwidth § Baseband limited by soundcard < 20 k. Hz § RF limited by FCC ISM band constraints § Filters, sampling rates, etc. Signal levels (RF, baseband DC) USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Signal Levels § § § Sensor to Baseband TX to IF TX to RF TX Wireless Link: RF TX to RF RX RF TX to IF TX to Baseband RX USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Signal Levels § § § § Sensor to Baseband TX to IF TX to RF TX Wireless Link: RF TX to RF RX RF TX to IF TX to Baseband RX Bottom Line: Sensor to PC § Can link be transparent to system? USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Signal Levels § § § Sensor to Baseband TX to IF TX to RF TX Wireless Link: RF TX to RF RX RF TX to IF TX to Baseband RX § Bottom Line: Sensor to PC § Can link be transparent to system? § DC requirements USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

References § § § Gagliardi, Introduction to Communications Engineering, 2 nd Edition. Rappaport, Wireless Communication Systems Ulaby, et. al. , Microwave Remote Sensing Telecommunication systems § www. directv. com § www. bluetooth. com, www. bluetooth. org Sensor systems § www. atstrack. com USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Two Month Course Schedule February § Week 4 (28 -1) § First progress report § Week 5 (4 -8) § Review peer reports § Week 6 (11 -15) § Preliminary Design Review § Week 7 (18 -22) § Weller at TTU March § Week 8 (25 -1) § Second progress report § Week 9 (4 -8) § Review peer reports § Spring Break (11 -15) § Week 10 (18 -22) § Critical Design Review § Week 11 (25 -29) § No TTU class (F) 1. All inputs are due on Friday of the specified week - no exceptions 2. Reviews of peer reports must be completed before the lecture on Friday USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY

Anything else? USF EEL 4935/TTU ECE 4720 SPECIAL TOPIC: WIRELESS SENSOR SYSTEMS Tennessee Tech UNIVERSITY