INSTITUT D ÉLECTRONIQUE ET DE TÉLÉCOMMUNICATIONS DE RENNES "#$ " UMR 6164

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1 ! "#$ " UMR

2 Cognitive Radio functional requirements Cognitive Radio system requirements Flexible radio UWB SDR and UWB SDR-compatible UWB Conclusion NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 2

3 Cognitive Radio functional requirements Cognitive Radio system requirements Flexible radio UWB SDR and UWB SDR-compatible UWB Conclusion NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 3

4 NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 4

5 Requirements spectrum analysis standard recognition, load, analysis of free bands channel sounding - geolocalization multipath propagation, distance, direction, movement vicinity characteristics time of the day, town, street available services, crowd/alone, dowloading channel availability user contracts, rights, preferences, inhabits, voice, face spectrum free access everywhere for all that As a 6 th sense for human beings Goal: make prediction requires enough information NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 5

6 Cognitive Radio functional requirements Cognitive Radio system requirements Flexible radio UWB SDR and UWB SDR-compatible UWB Conclusion NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 6

7 A cognitive radio system is a flexible radio (Software Defined Radio SDR) That can take decisions autonomously transparently, without user action Thanks to sensing means smartness Not only spectrum! SDR communication sub-system NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 7

8 Sensing means!! SDR communication sub-system NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 8

9 Smart!!! smart sub-system SDR communication sub-system NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 9

10 " Focus on flexible radio interest of a SDR UWB system impact on UWB approach SDR UWB possible implementation sensing means larger than only spectrum aspects Smartness is not in the scope learning analysis decision NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 10

11 Cognitive Radio functional requirements Cognitive Radio system requirements Flexible radio UWB SDR and UWB SDR-compatible UWB Conclusion NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 11

12 #$ NEWCOM Project D and Department 4 focused on flexible radio in NEWCOM I will to extend towards CR in NEWCOM II NEWCOM I Project D 3 clusters WPRD.1: algorithms WPRD.2: platform WPRD.3: QoS Project D WPRD.2 joint with Department 4 NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 12

13 #$% Static reconfiguration bug fixing upgrade multi-standard Dynamic reconfiguration adaptation to transmission conditions QoS optimization frequency switching standard hand-over Flexible radio only: invoked by the network Cognitive radio: by the system itself also NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 13

14 #$% Software enabling technologies for FR At design time design tools OS, compiler, co-design, abstraction, ASIP, signal processing, simulation, parameterization and common operator configuration management SW architecture, P-HAL, distributed hierarchical management, SCA During operation software architecture P-HAL, distributed hierarchical management, SCA hardware management Partial dynamic reconfiguration of FPGA NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 14

15 #$%& Hardware enabling technologies for FR digital conversion wideband A/D, D/A amplification wideband amplifier digital processing processor architecture FPGA architecture analog front-end multi-standard wideband antenna Main issues: bandwidth (BW) and computation speed Critical for a SDR- compatible UWB NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 15

16 Cognitive Radio functional requirements Cognitive Radio system requirements Flexible radio UWB SDR and UWB SDR-compatible UWB Conclusion NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 16

17 %$' Historically implulse radio (IR) for low data rate (LDR) low cost, low power, multiple LDR applications superposed but neutral to other transmission (neither polluating, nor being polluted) FCC mask February 2002 IEEE a (since end of 2002) high data rate (HDR) IEEE a (since 2004) low data rate NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 17

18 ( UWB intrinsic features wide-band IR (channel sounding, positionning, low power consumption) From low data rates To very high data rates Unlicensed Superposition with existing standards does not interfere / not jammed by others spread spectrum techniques (noise) Network of sensors (very low-cost: numerous) Ad-hoc networking NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 18

19 ) '' IEEE a high data rate based on existing technos MB-OFDM vs DS-CDMA failed towards a de facto standard not low cost, low power expected interference matters CEPT position IEEE a low data rate - ongoing Based on existing knowledge OFDM, DS-CDMA, FH-CDMA not a completely dedicated new approach NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 19

20 Cognitive Radio functional requirements Cognitive Radio system requirements Flexible radio UWB SDR and UWB SDR-compatible UWB Conclusion NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 20

21 *+ CR would greatly benefit of a SDR UWB combine all UWB features - multi-purpose UWB necessity of a digital back-end (SDR-like) A priori incompatible because of the BW even with usual techniques UWB implementation is tough SDR current implementations only deal with narrow BW UWB context: reconsider Software Radio no more A/D as close as possible of the antenna analog RF front-end required NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 21

22 SDR is incompatible with IEEE a UWB candidates sampling constraints processing power constraints solutions in direct opposition with low-cost basis of UWB A compatible solution with SDR: Mitsubishi Electric ITE UWB architecture reconsider the issue of UWB to relax HW constraints with performance equivalent to UWB demand finally: so relaxed that can easily target SDR respect original goal: low cost, low power NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 22

23 Cognitive Radio functional requirements Cognitive Radio system requirements Flexible radio UWB SDR and UWB SDR-compatible UWB Conclusion NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 23

24 #% Mitsubishi Electric ITE courtesy Major objectives of Mitsubishi ITE approach relax HW constraints without decreasing performance High data rate - HDR multi-band impulse radio based on energy detection Rethink UWB paradigm for HDR Low data rate - LDR ultra-wideband impulse radio based on energy detection on a single wide band multi-purpose architecture: channel sounding, positioning, synchronization... Generalized UWB approach for LDR related application NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 24

25 UWB channel many paths (>10) delay spread Td: several tens of ns Modulation OOK modulation impulses of 2 ns Receiver & Channel Td non-coherent data recovery (energetic) relaxed sampling time adjustment relaxed linearity constraints (analog) integration time Ti in function of the channel delay spread Td relaxed sampling frequency relaxed digital post-processing speed Tr Mitsubishi Electric ITE courtesy Ti ( )² i 0 Low cost & low power usual integrated technology 1 0 NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 25

26 Multi-band UWB & the diversity offered by the channel is enough at a BW of ~250 to 500 MHz to increase data rate (use bands in parallel) to adapt to any location configuration to adapt to evolutive environment (hop) to respect any mask Mitsubishi Electric ITE courtesy On each sub-band: - sampling rate: ~30 MHz - resolution: 4 to 8 bits - sync. accuracy: ~2 ns Compared with coherent solutions 3 to 5 db loss compared to theoretical coherent receivers for the same amount of collected energy 24 sub-bands of 250 MHz 600 Mbits/s at 5 m Ti = 30 ns for 10-5 of BER Corresponding coherent receiver complexity is very challenging as it should intercept 40% of the energy with high multipath resolution ISI avoidance high order modulation real-time channel estimation >10 paths processing real-time channel tracking NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 26

27 Band GHz 0.2 ns impulses no need to process at the impulse width scale use integration effect of spreading techniques over a longer interval (inter-chip duration τ) Processing gain can be adjusted distance may be very long by simply increasing the length of the time hopping code,- B Mitsubishi Electric ITE courtesy TH code τ τ τ T ( )² pulse width ~0.2 ns T ~2 ns τ=τ2-τ1 ~100 ns 1 2 N p 0 Signal detected No signal detected NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 27

28 ,- Mitsubishi Electric ITE courtesy Relaxed implementation constraints sampling frequency ~10 MHz LDR analog front-end can be used for other purposes than data transmission Positioning position, speed, direction Channel sounding detection, channel estimation Synchronization help of the HDR is investigable to be coupled with high data rate structure NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 28

29 .% SDR paradigm should be changed not digitize as close as possible to the antenna too demanding in terms of technology, power consumption, heat dissipation a too high digitisation rate for A/D and D/A, a too high processing rate for DSP, FPGA Analog pre-processing as much passive as possible a new way of extracting information from the channel when possible (future standards, ) Some kind of analog computing NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 29

30 Cognitive Radio functional requirements Cognitive Radio system requirements Flexible radio UWB SDR and UWB SDR-compatible UWB Conclusion NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 30

31 '! - Impulse radio UWB provides to CR system - unlicenced radio connections for LDR and HDR - legacy systems interference compatibility - sensor by itself - low power consuming - UWB HDR provides to CR system - ultra-fast OTAR channel if necessary - free bands identification - standard bands occupation - multi-band to adapt to any mask at any location, dynamic spectrum allocation NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 31

32 '!! UWB LDR provides to CR system - position, speed, direction and radio activity of other terminals or radio communication devices in the area - connection with networks of sensors all around - area information from a hot-spot - cooperation with other terminals to share info - ad-hoc connectivity w other terminals / parallel networks - Back to the CR bubble example: Safety radio bubble benefits from UWB to make predictions and take adequate decisions NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 32

33 NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 33

34 UWB: good potential contributor to CR unlicensed connectivity Interference less sensing and sounding means (multipath channel, spectrum occupancy, positioning, direction, speed) HDR for fast over-the-air download multi-band HDR for frequency flexibility LDR communication link for a ubiquitous connectivity connection with surrounding networks of sensors low power consuming NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 34

35 SDR UWB and Cognitive Radio An Ultra-Wide Band Umbilical Cord for Cognitive Radio Systems Christophe MOY, Alexis BISIAUX, Stéphane PAQUELET IEEE PIMRC 05, Berlin, Germany, September 2005 SDR-compatible UWB solution A SDR Ultra-wideband Impulse Communication System for Low and High Data Rates C. MOY, S. PAQUELET, A. BISIAUX, A. KOUNTOURIS SDR Forum Technical Conference, Phoenix, USA, November 2004 HW complexity considerations of the high data rate structure "RF Front-End Considerations for SDR Ultra-Wideband Communications Systems" Stéphane PAQUELET, Christophe MOY, Louis-Marie AUBERT RFdesign magazine, July 2004 Theoretical principles of the high data rate structure "An Impulse Radio Asynchronous Transceiver for High Data Rate" Stéphane PAQUELET, Louis-Marie AUBERT, Bernard UGUEN Joint UWBST&IWUWBS 2004, May 2004, Kyoto, Japan. NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 35

36 - a CR terminal will ideally have in its vincinity many kinds of information at its disposal to take adequate decisions, adapt its behavior for a given service - available standards in the area - rate of use of standards - free bands identification and related info of standard availability - other terminals or radio communication devices in the area: their position, speed and direction, their radio activity (sounding) - so that it can make a prediction of the rate of use of the standards - user information on the area (other sensors of any kind) - as well as the traffic law and the indicators or stop lights of a car helps a driver to anticipate on the road - a terminal that switches off is like a car that parks - a terminal that changes of band should put its indicators - a terminal that connects to a video conferencing service is like a big truck on a small road - Safety bubble in the sense that a communication may arrive safe at the Rx - convenient QoS, no interference for him and the others - warns about dangers (imminent saturation of a band) - terminal bubbles may overlap - cooperate with oher terminals in an ad-hoc way in order to share CR infos - other transport analogy - the current standard-oriented situation is comparable to the of a train that must follow the rails - whereas a CR terminal will be able to choose any path to go to its destination NEWCOM Workshop at IST Mobile Summit June 2006 Mykonos - Greece 36