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1RFCM 103: Bluetooth Basics Technical data is subject to change Copyright@2003 Agilent Technologies Printed on Dec. 4, 2002 5988-8500ENA Welcome to the “Bluetooth Basics” module presented by Agilent Technologies. We believe you find this presentation useful as an introduction to a technology that is quickly gaining acceptance world wide. Bluetooth Basics Bluetooth technology eliminates the need for cable connections and facilitates fast and secure transmission of voice and data between enabled devices. There is unprecedented market interest in this technology and its applications. It’s an evolving uniform standard for wireless connectivity and interoperability that’s already supported by a great deal of documentation, but there are still many integration and test issues yet to be resolved. In this module you’ll learn about the basics of how Bluetooth works, its potential applications, and discuss the current expectations for implementation and market acceptance. 2•Market Drivers •Applications •The Bluetooth Standard and Qualification •Technology Implementation •Competing Technologies Agenda In this module, we’ll look at what’s creating the need for Bluetooth technology, where it’ll be used, more on the standard itself. We’ll start the presentation with an overview of the market and discuss the factors that are driving the acceptance of this technology and the growth its market. Current and potential applications will be presented and described. The major elements of the Bluetooth Standard reviewed along with the qualification process. The implementation of the technology is given and we finish with a comparison of competing technologies The cabling and configuration required to have these all talking to each other is not insubstantial, and furthermore, inconvenient if you want to change your configuration or have them talk to devices in both home and office (moving cables, installing software etc.) Enter Bluetooth. Add a small unobtrusive and (soon to be) inexpensive module & antenna to each one, and you have an instant connection to all other Bluetooth devices (that you choose to be connected with) within the designated boundary. ============================================================= Note: This Agenda is shown only at this point in the presentation. There is no delineation between topics within the presentation. The Technology Implementation section has its own sub-agenda. 3Market Drivers: Mobile Phones APPLICATION DFashion DHands-free operation STRATEGIC D Introduction of new product families D Alleviate 3G battery / weight issues D Possible relief for safety concerns D Add premium features Applications that are likely to benefit from the integration of Bluetooth are cell phones, PDA’s, digital cordless phones, digital cameras, adapters, PC Cards, dongles, headsets, PCs, printers and faxes, and so on. It is predicted that over 1.5 Billion Bluetooth-enabled devices will be in use by 2005! We utilize a compliment of handheld/mobile devices that each need to be able to connect to at least one other device in order to utilize their full functionality. One of the first applications developed are Bluetooth headsets for use with, among other things, mobile phones. Ericsson and Nokia are two leading proponents of integrating Bluetooth technology into their 3G mobile phone products. Nearly all of the world’s mobile phone manufacturers are Bluetooth adopters. This technology is a significant and perhaps essential element of their 3G development and marketing plans. Bluetooth will allow completely new combinations of innovative products and allow new premium features to be added to mobile phones. 4Market Drivers: PCs, Laptops & Peripherals APPLICATION DTalk to portable devices DConvenient low / medium rate data transfer, RS232, USB, Ethernet? DData synchronizing DCell phone links for laptops / palmtops STRATEGIC DNew products for the market DIR function that is user friendly DDon’t assume Bluetooth will be the only Wireless interface for LAN DCost effective product differentiation, leading to a customer expectation Even desktop PCs will benefit from being able to “talk” to peripheral devices such as a digital camera, printer, mouse, or modem. A notebook PC can synchronize appointments with the PDA, back up its files on a shared zip drive. A phone would be able to automatically dial phone numbers stored on either the PDA or Notebook. The infrared organization is working with the Bluetooth S.I.G., so that Bluetooth learns some lessons, but also IR will benefit from improvements in Software support / ease of use. 5Potential Market Size 0 200 400 600 800 1000 1200 1400 1600 1999 2000 2001 2002 Everything else Cameras Peripherals PDA's Desktop access. Desktops Cordless phones Laptops Cellular phones 2/3 of the potential market is outside mobile phones Annual sales [Millions of units] [Dataquest] This shows the number of units that COULD use Bluetooth as an interface. You may need to study a printed slide to see all the detail. Bluetooth technology is not necessarily a good fit for Wireless LAN, because it has limited bandwidth & is basically not meant for situations with multiple “masters” calling some other device. It doesn’t have to be Bluetooth OR some other wireless data technology. If price is right, may well get more than one. Of course, there will still be several ways to solve connection problems. Cables, infrared and memory sticks aren’t going away overnight. As noted in a previous slide, the utility of a desktop PC will be enhanced with the addition of Bluetooth. This will either be as an interface to portable devices, or as a convenience to reduce wiring to peripherals. We expect two-thirds of the Bluetooth market to be outside the mobile phone. Either this is for things the phone talks to, or simply other devices making use of a low cost cordless link. 6Three-in-one Phone Network Access Bridge Interactive Conference Ultimate Headset Laptop Speakerphone Briefcase Trick Forbidden Message Automatic Synchronizer Instant Postcard Cordless Desktop Hurry up! This dog is heavy! Now, where’s the Mini- bar... Usage Models THE THREE-IN-ONE PHONE. Use the same phone wherever you are. When you're at the office, your phone functions as an intercom (no telephony charge). At home, it functions as a portable phone (fixed line charge). And when you're on the move, the phone functions as a mobile phone (cellular charge). THE INTERNET BRIDGE. Surf the Internet regardless of the connection. Use your laptop to surf the Internet wherever your are, and regardless if you're cordlessly connected through a mobile phone (cellular) or through a wire-bound connection (PSTN, ISDN, LAN, xDSL). THE INTERACTIVE CONFERENCE. Connect all participants for instant data exchange. In meetings and conferences, you can share information instantly with all participant, and without any cord connections. You can also cordlessly run and control, for instance, a projector. THE ULTIMATE HEADSET. A cordlessly connected headset keeps your hands free at all times. Connect your headset to your mobile or any wire-bound connection to keep your hands free for more important tasks when you're at the office or in your car. THE LAPTOP SPEAKERPHONE. Use your laptop as a speaker phone wherever you are. Connect cordless headsets to your laptop and use the lap top as a speaker phone regardless of whether you're in your office, in your car or at home. THE BRIEFCASE TRICK. Use e-mail while your laptop is still in the briefcase. When your laptop receives an e-mail, you'll get an alert on your mobile phone. You can also browse all incoming e-mails and read those you select in the mobile phone's window. THE FORBIDDEN MESSAGE. Write e-mails on your laptop while you're on an airplane. As soon as you've landed and switched on your mobile phone, all messages are immediately sent. THE AUTOMATIC SYNCHRONIZER. Automatic background synchronization keeps you up-to-date. Automatic synchronization of you desktop, laptop, notebook (PC-PDA and PC-HPC) and your mobile phone. For instance, as soon as you enter your office the address list and calendar in your notebook will automatically be updated to agree with the one in your desktop, or vice versa. THE INSTANT POSTCARD. Send instant photos and video clips from any location. Cordlessly connect your camera to your mobile phone or any wire-bound connection. Add comments with your mobile phone, a notebook or your laptop and send them instantly to a receiver anywhere in the world. Suitable for professional as well as personal use. THE CORDLESS DESKTOP. Connect all peripheral tools to your PC or to the LAN. Cordless connection of your desktop or laptop to printers, scanners and to the LAN. Increase your sense of freedom in everyday work by cordless connection of your mouse and keyboard to your PC. 7Example Bluetooth Module [CSR September 2000] This is a picture of the Cambridge Silicon Radio (CSR) solution. Little extra is required to turn it into a wireless headset or some other target application. Further integrated solutions are in work and will shortly allow the entire radio to reside on a single chip [except for perhaps the crystal and the battery!]. 8Acronyms Bps Bits per second BGA Ball Grid Array BQRB Bluetooth Qualification Review Board BQA BT Administrator BQTF BTQ Test Facility BQB BTQ Board BTAB BT Advisory Board FHSS Frequency Hopping Spread Spectrum GFSK Gaussian Frequency Shift keying ISM Industrial, Scientific & Medical LTCC Low Temperature Coefficient Ceramic Carrier SIG Special Interest Group TF1 Task Force 1 TF2 Task Force 2 TF3 Task Force 3 TCP/IP Transmission Control Protocol / Internet Protocol HID Human Interface Driver L2CAP Logical Link Control and Adaptation Protocol LMP Link Manager Protocol NF Noise Figure This list of acronyms is provided for your reference. 9Promoters, Associates & Adopters Promoters are a group of large companies driving the technology into the market : Ericsson Nokia Toshiba Intel IBM 3Com Lucent Motorola Microsoft • Over 2000 companies have become adopters of the technology • Bluetooth Special Interest Group (SIG) • Associate membership A Special Interest Group [SIG] has been formed to advance the acceptance of Bluetooth. It is commercially backed [not government, like ETSI]; largely by the companies above that are referred to as the Promoters of Bluetooth. They are in charge of the development of specifications, as well as their own products. As well as promoters there are companies called the adopters. Currently there are over 2000 companies that bear no financial responsibility but have pledged to adhere to the standard when developing Bluetooth products. Another category of membership that lies between the previous two is that of Associate. Associates bear a portion of the financial support required by the SIG, in turn they participate in the development of the standard and the associated profiles. The wide range of interests these companies have, means there are some conflicting priorities. An example is the proposal before the US FCC for a 1 watt specification as part of 802.11. The Bluetooth SIG are finding it difficult to give a united response, because some members will find this useful. This is despite the fact Bluetooth itself will suffer more interference. 10 The Standard Has two parts: • Core • Profiles Currently at Version 1.0b. Version 1.1 imminent. Version 1.1 corrects errata - not backwards compatible with 1.0b. Main effort now in profiles. GLOSSARY L2CAP - Logical Link Control and Adaptation Protocol LMP - Link Manager Protocol A the time of this writing, the current released version of the Standard is version 1.0b with version 1.1 in review. 11 Bluetooth Qualification [Bluetooth.com 2000] The Bluetooth SIG Qualification hierarchy. 12 The Qualification Process ADOPTER (MANUFACTURER) BQB BQA BQTF Qualified Products List Qualification programme documents BQABluetooth Qualification Administrator BQBBluetooth Qualification Board BQTF Bluetooth Qualified Test Facility Test Report Checked by BQB Documents pulled from web site Product Tested Declarations & Documentation reviewed Ericsson hold the rights to use the Bluetooth name & logo. They will not allow other organizations to use it unless equipment has been through this qualification process. “Interoperability”, devices working together properly, is what will make Bluetooth really succeed. This involved process is one way the SIG is trying to build interoperability into the system. Adherence to the qualification process will be about half the battle to get Bluetooth widely accepted. The rest will be down to market acceptance that in turn will drive the engineering investment. This is similar to the way the computer software market works. Alongside the formal process shown here, the SIG are organizing “unplugfests”. Companies with devices to test can go to these large technical meetings and find out how well their product works with everyone else’s products. 13 The Bluetooth Stack / Main Functional Blocks Profiles Making a Bluetooth link Bluetooth RF Piconets & Scatternets Packet Format Bluetooth Technology Overview Technology overview agenda. 14 The Bluetooth Stack RF Baseband Link Manager L2CAP TCP/IP HID RFCOMM Applications Data Co nt ro lAudio Flow control, Multiplexing, Segmentation, Reassembly Serial Port Emulation Asynchronous Links Synchronous (voice) Links GLOSSARY TCP/IP - Transmission Control Protocol / Internet Protocol HID - Human Interface Driver L2CAP - Logical Link Control and Adaptation Protocol LMP - Link Manager Protocol HCI Logical Link Control & Adaptation Protocol  Segmentation & Reassembly  Multiplexing  Quality Of Service Here we have an overview of the complete Bluetooth protocol stack. Two distinct types of connection between devices are supported: synchronously using the audio layer, and asynchronously going through the data layer. Bluetooth actually supports data and voice simultaneously. The application layer has access to TCP/IP for web browsing/ftp etc. The obvious use here is surfing the internet from your PDA or Notebook. The RFCOMM layer, for serial port emulation, would be used to connect devices not equipped with Bluetooth, but have a serial connection. A synchronous link connected directly to the baseband processing layer is used for voice transmission. Data are transmitted on asynchronous links and are managed though the L2CAP (Logical Link Control and Adaption Protocol). The link manager protocol (LMP) applies flow control, packet assembly and multiplexing services. At the lower levels, the baseband layer forms the basic modulating signal and the RF layer provides the physical transport mechanism for the modulated signal. 15 The Main Functional Blocks Host Processor RF Transceiver BasebandProcessor Flash Memory RFIC uC (SW) BSIC Host Controller Interface IO System IO SUBSTRATE Bluetoth Module Could be a single IC Bluetooth Module A Bluetooth system requires these basic blocks, but there are many different ways to implement it. Application Software lies beyond the the Host processor, depending on the Profile(s) supported. Both CMOS and SiGe are being used for the radio itself. Performance, power and die size being the variables that get traded. The Baseband is typically being quoted as taking 70,000 gates. 16 •Generic • Generic Access, Service Discovery •Serial • Serial Port, Generic Object Exchange, File Transfer, Object Push, Synchronization •Telephony • Cordless Telephony, Headset, Intercom •Networking • Dial Up Networking, Fax, LAN access Profiles A profile defines what is needed at the Host level to support particular applications. Profiles have their own part of the specification, that runs to more than 400 pages. GAP (generic access) and SDAP (Service Discovery) are common parts to many if not all of the other profiles. It turns out that these were defined later than some of the others after the SIG working groups realized there were common elements within the application profiles. 17 Bluetooth State Diagram STANDBY TESTMODE CONNECTED [Active] PAGE [3200 hops/sec] INQUIRY [3200 hops/sec] TEST MODE NEEDS TO BE LOCALLY ENABLED IN DUT The Bluetooth address is a unique 48bit address assigned to each device Standby - Waiting to be told to join a piconet Inquire - Ask about radios to connect to. Inquirer transmits two short [68us] packets twice in one 625us period. The listener, listens every 1.28 seconds Page - Connect to a specific radio. Similar to Inquiry, but paged device’s address is sent, which reduces the time to connect, to around 2.5 seconds. Connected - Actively on a piconet (master or slave) [ Bluetooth defines four Connected modes: Active, Sniff, Hold and Park. These allow dynamically settable alternatives in responsiveness to the Master and power consumption. Park is the lowest power. ] Park/Hold - Low Power connected states Bluetooth also defines a Test Mode that allows the Test Set to control the DUT. [ e.g. turn off frequency hopping ] 18 z Operating Frequency: ISM band 2.402 - 2.480 GHz z Number of carriers: 79 carriers at 1 MHz spacing z Frequency Hopping: nominally 1600 hops/s z Modulation: 0.5 BT GFSK modulation z Raw Symbol rate: 1 Mb/s z 3 Power Classes:Nominally < 0dBm, 0dBm, +20dBm z Reference sensitivity: -70dBm, but some designs claiming -90dBm Radio Parameter Overview Bluetooth devices operate in the ISM (Industrial, Scientific & Medical) band, on 79 channels from 2.402GHz to 2.479GHz. They communicate with each other using a digital frequency modulation method known as 0.5 GFSK. This means that a carrier is shifted up nominally 157kHz to represent a ‘1’ or down to represent a ‘0’, at a rate of 1 million symbols (or bits) per second. The ‘0.5’ (Bandwidth Time) sets the -3dB bandwidth of the data filter to 500kHz. This is used to limit the RF spectrum occupied. Data rate (including protocol overhead) is around 700 kbps/sec Communication between two devices is Time Division Duplexed, meaning that the transmitter and receiver alternate their transmissions in separate timeslots, one after the other. In addition, a very fast frequency hopping scheme (up to 1600 hops/sec) is employed to aid the reliability of the link in what is likely to be a crowded band. Recent U.S. FCC rulings indicate the band use is only going to increase. Did you know: Microwave Ovens operate in this frequency band, but only use one half of the the line cycle Several suppliers looking to offer 20dB better Rx sensitivity for non-interference limited applications 19 Waveform Characteristics 11 0 0 1 0 Center Freq. + f - f 1 1 0 0 1 1 1 0 00 0 0 0 0 0 0 00 0 1 1 11 1 1 11 1 1 • Peak deviation +/- 157.5 kHz (nominal) • 1 Million bits/sec • Modulation index = 0.28 - 0.35 • ‘1010’ deviation approx. 88% of max due to 0.5 BT Filter • 500 kHz rate of modulation (2 bits per cycle) The Carrier Wave (CW) is modulated by shifting it up 157.5 KHz to represent a ‘1’ or down 157.5 KHz to represent a ‘0’, all at a rate of 1million bits per second. The 0.5 BT Guassian filter is used to limit spectral spread, thus allowing a 1 MHz channel spacing. The effect of this is that higher frequency bit patterns I.e. ‘1010’ experience less deviation than long trains of 1’s or 0’s. Note that although we get 1 million bits/sec, the fundamental rate of modulation is actually only 500 KHz because we get 2 bits per cycle. 20 •5 different hopping sequences, 4 of which are short (32 hops) and used for special purposes e.g. connection establishment •Main sequence called “Connected Mode” sequence • 134,217,728 hops (2^27) • 1600 hops/sec over 79 channels • Why have it? FCC requires either FHSS or DHSS. Aids signal reliability in a potentially crowded band Hopping in Detail There are 5 different hopping sequences, although 4 of them are used for special p