ICT | Software Defined Radio : enjeux et perspectives par Sylvain Azarian et Jonathan Pisane | Liege Creative, 13.12.11
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ICT | Software Defined Radio : enjeux et perspectives par Sylvain Azarian et Jonathan Pisane | Liege Creative, 13.12.11

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Les communications sans fil prennent une place prépondérante dans la société de l’information. Les besoins toujours croissants de débit, de qualité et de couverture réseau imposent de revoir ...

Les communications sans fil prennent une place prépondérante dans la société de l’information. Les besoins toujours croissants de débit, de qualité et de couverture réseau imposent de revoir entièrement les modèles techniques et économiques des outils actuels.
INTELSIG, service de Traitement du Signal de l’ULg et son partenaire, la grande école d’ingénieurs française SUPELEC (Ecole supérieure d’électricité) nous en diront plus sur la radio-logicielle (Software-defined radio), une des technologies retenues pour apporter une solution à toutes ces contraintes.

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    ICT | Software Defined Radio : enjeux et perspectives par Sylvain Azarian et Jonathan Pisane | Liege Creative, 13.12.11 ICT | Software Defined Radio : enjeux et perspectives par Sylvain Azarian et Jonathan Pisane | Liege Creative, 13.12.11 Presentation Transcript

    • Parole d’expertSoftware Defined Radio : enjeux etperspectivesIr Jonathan PISANE, Doctorant ULg - INTELSIGIr Sylvain AZARIAN, Ingénieur de Recherche - SUPELEC
    • Avec le soutien de :
    • Software Defined Radio : Challenges and Opportunities Sylvain AZARIAN - Supélec Jonathan PISANE – Ulg / INTELSIG - SupélecSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 1
    • Talk outline •  Part I – Introduction to SDR –  Need for new system architectures –  SDR as a potential solution –  Basics to understand how it works –  Demos •  Part II – SDR in OUFTI-1 Satellite •  Part III – Radar applications –  What is radar ? –  “Active” and “passive” radars –  Using passive radar techniques to collect RCS •  Introduction to J. Pisane PhD work •  System presentation •  Live demo •  Results •  Part IV– Challenges –  Balancing technical constraints –  Possible issues –  Consumer Electronics and product life-cycle •  Part V – Future mobile Networks –  Quick presentation on active research topics for future mobile networksSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 2
    • Part I 1 – Introduction to Software Defined RadioSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 3
    • Communication system A communication system takes input message A at transmitter side and delivers it at receiver side. On transmit side, a modulator is used to encode the information to be transmitted by the carrier. This information is then extracted using a demodulator at the receiver. This message can be analogical (voice, image) or digital (data). 0 1 0 1 ….. 1 Message A Modulator Demodulator 0 1 0 1 ….. 1 Message A time time Osc. Osc.Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 4
    • Frequency allocation plan (USA)Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 5
    • Spectrum allocation… spectrum saturation Currently, spectrum is allocated on a « per usage » basis. Ideal for broadcasting systems, this scheme is no longer efficient when spectrum is saturated and new « point to point » communication is required. Dynamic spectrum Access is a possible solution to this saturation. New allocation rules… new techniques… new challengesSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 6
    • The limits of « classical hardware design » One technology => one chip • GSM • GPRS • UMTS • 4G fit ! • WiFi Doe s not • BlueTooth • WiMAX • …Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 7
    • Lack of space for new wideband telecoms Allocated band : not available HF VHF Need for more throughput => need for more bandwidth … where ???? One solution : bandwidth aggregation •  Design modulations and RF chains able to transmit on sparse spectrumSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 8
    • Stacking RF technologies – Cell. phones RF modules – Nokia X6 •  Phone CDMA •  WiFi •  BlueTooth •  GPS •  Close in frequency, but completely different systems ►one chip by function ► cost and battery life…Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 9
    • Stacking RF technologies – Broadcast radio receivers One sub-circuit by modulation type… Adding a new modulation means redesigning the hardwareSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 10
    • Using applications to replace hardware •  Wide bandwidth •  High resolution AD & DA converters •  Sample signals from 1µVolt to 50 mVolt with constant linearity… •  Tunable power, tunable gain, … •  Unlimited speed to main application.. SDR technologies bring a new approach to have one hardware for allSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 11
    • Sampling signal to process it by software RF signal Continuously varying voltage from the antenna 0010101010101000 0111010101111010 0100010010001001 … 0100010011011100 Bit stream Sampling clock (defines the zoom level on the incoming signal) Analog to digital converter (ADC) : at each top given by sampling clock, a picture of the incoming signal is taken and delivered as a binary word.Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 12
    • Basic SDR system architecture Analog world Digital world ADC DAC CPU Software Defined Radio equipment : •  Antenna and basic filtering, •  Analog to Digital conversion, •  CPU + applications.Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 13
    • Communication system - Modulation Signal modulation involves changes made to sine waves in order to encode information. The mathematical equation representing a sine wave is as follows: We see we have two variables we can use separately : amplitude and angle. Each modulation technique (AM,FM,…) uses a different scheme to change these variable depending on the information to send. In a digital communication system, the information transmitted is called the baseband.Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 14
    • Modulation – one example ASK (OOK) – Amplitude Shift Keying – playing with amplitude In this modulation scheme, we change Ac depending on the bit value to transmit. We can use two levels or on off keying (OOK). Modulator time Osc. Demodulation is quite easy but this method is very sensitive to parasites.Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 15
    • Quick introduction to the theory… why I & Q ? Signal spaces and basis functions Basis : Two orthogonal functions chosen as basis set : sine and cosine. Signal space : Let s define our message M(t) as a two-dimension vector M(t)={x(t) ; y(t) } We can represent our message on a 2D plane using Cartesian or polar coordinates. Q M(t) M(t) I In our signal space, we have the horizontal axis called I (in phase) and vertical axis called Q (in quadrature). We can also use complex numbers to represent our messages : M(t) = S.ejɸSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 16
    • Digital modulation Using a predefined dictionary (constellation), each sub-block of bits is mapped in IQ plane : Ex: QAM16 0 1 0 1 ….. 1 The corresponding I and Q values are then used to generate baseband time signal. Of course the dictionary must be shared by transmitter and receiver… One can imagine a complete set of constellations to map bits to symbols :Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 17
    • Digital transmitter architecture Back to our RF chain… Polar modulator , quite complex to realize in hardware because requires evaluation of :Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 18
    • Digital transmitter architecture Quadrature modulator Quadrature modulator is the most common design used in digital communications. To increase communication throughput, this scheme can also be parallelized on multiple frequencies simultaneously. OFDM uses multiple carriers, carefully chosen, to transmit bursts of data.Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 19
    • Digital receiver architecture Quadrature receiver Minimalistic architecture for quadrature signals recovery: Incoming signal is projected (multiplied) with our two basis functions (sin & cos) to retrieve projections over I and Q axis in our signal space. CPUSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 20
    • Introducing demo #1 – SDR Dongle from Microsat RF amplifier USB bridge Antenna socket Analog to Digital converter RF Tuner No signal processing is done aboard : Samples are sent to host PC via USB and need to be processed to extract information.Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 21
    • HDSDR : Software Defined Receiver application frequency Waterfall display time spectrum display Zoom areaSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 22
    • Demo #1 : Ingredients •  See it working… PC easySDR USB dongle From microsat WinRAD : Multimode SDR decoding freewareSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 23
    • Part II 2 - SDR In OUFTI-1 SatelliteSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 24
    • MS Thesis A. Dedave •  Implementation of FM, AX.25 and D-STAR radiocommunication protocols on SDR •  Feasibility study for future nanosats •  Develop SDR experience @ULg – MontefioreSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 25
    • Analog RF front-end: RxSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 26
    • Analog RF front-end: TxSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 27
    • Digital back-end: Tx & RxSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 28
    • Application (1): D-STAR – Rx & TxSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 29
    • Application (2): AX.25Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 30
    • MS Thesis A. Dedave: DemosSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 31
    • Part III 3 - Radar applicationsSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 32
    • Definition and application RADAR = RAdio Detection And Ranging transmit & receive E.M. waves detect the target provide localization (range, angle, velocity) can provide classification, identification of target Military Civilian air surveillance (surveillance and tracking ) air traffic control (ATC) maritime surveillance maritime navigation control battlefield surveillance collision avoidance missile seeker guidance & interception satellites tracking imagery road traffic control & ERP archaeological & geologic researchSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 33
    • Radar in the day to day life 200 to 400km 360km Air Traffic Control and Weather Radar monitoring http://www.meteox.com/h.aspx? r=&jaar=-3&soort=loop1uur Maritime Surveillance 200 to 400km Road Traffic Control Radar Presence Detection (Domotic) 10 to 40km 10 to 40 m 10 to 30 mSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 34
    • Less popular but so useful… 50 to 140km Fighter control radar AWACS Early Warning Surveillance > 400km Through the wall radar 1 to 10 m Imaging & remote Sensing from the earth 200 to 400 km Air Defence Radar 700 to 1000 kmSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 35
    • Radars you haven’t imagined… Very Long range skywaves radar 1000 to 3000 km 1 to 80 km Passive RadarSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 36
    • Radar principle Emitted signals Peak power : Pe (~ 1 kW à 1 MW ) Average power : Pm (~ 100 W à 10 kW ) t - Pulse duration (~1 à 100 ms) Received Tr - Pulse period (~100 ms à 10 ms ) Dt - Pulse delay, used to retreive the range D Dt = 2D/c The antenna beam is narrow and scanning 1 to 3° all directions This allows for measuring the target direction Scanning 10rpmSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 37
    • Passive radar Passive radar relies on existing transmitters (donors). By processing reflected and direct path signal, it is possible to compute target position and speed. For this specific application, SDR offers the possibility to receive any type of donor.Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 38
    • Introduction to J. Pisane PhD work SN533, A320 transponder on Unknown aircraft ? transponder off SN533, A320 ? Radar Goal of Ph. D. thesis: Identify the ?’sSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 39
    • Introduction to J. Pisane PhD work Receiver 3 GSM Receiver 2Emitters of opportunity Receiver 1 •  Operate at "low frequencies" (<1GHz) •  Data = RCS of targets •  No image reconstruction DVB-TSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 40
    • Using passive radar techniques to collect RCS System overview Software Defined Receiver Network (direct or Internet) Network (direct or Internet) Software Defined Receiver remote Apache Tomcat Donor supervision (VOR, FM station, …) Geo database Donors & Receivers SDR controller USB or remote Donor (VOR, FM station, …) Central system Data collection / storage / analysis Kinetic SBS-1 MySQL ADSB-B decoder ADSB ReceiverSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 41
    • RCS Data collection: System overview Position given by ADSB receiverSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 42
    • RCS Data collection: System overview Receiver tuned on a quiet area of the spectrum to have good SNR Software Defined ReceiverSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 43
    • RCS Data collection: System overview Samples Decimation New We keep Old samples samples around 1second of signal shift FFT ‘Direct Path’ signal : spectrum of original transmitted signal ‘Echo path’ : same signal delayed and shifted (Doppler effect) Axe Y SNR ! Frequency (FFT bin)Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 44
    • RCS Data collection: System overview Live demo ! (if it works  )Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 45
    • Typical spectrogramSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 46
    • Recovered RCS of planeSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 47
    • Part IV 4 - Software Defined Radio: challengesSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 48
    • Market driven by « Consumer Electronics » Each iPhone® gives $300 operational profit… More than 8MILLIONS units sold in 2010 => 300x8000000 = 240 Million$ Current designs are Keep it simple, Keep it low cost new models every 6 month, design driven by marketing teamSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 49
    • Balancing a set of constraints Wideband signals => Wide bandwidth High frequency => High sampling rate Huge amount of data to process in real-time System design is complex =Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 50
    • Processing power •  SDR system to process WiFi signals •  One channel is 22MHz wide, sampled at 44 MSPS at 16 bits (I and Q) gives : –  44M * 4 bytes / seconds ➜ 176 MBytes/seconds ➜ Too much data to be processed by a « PC » processor ➜ Specific pre-processing hardware required (FPGA, DSP…) ➜ Such system require hardware + software + radio engineers to work togetherSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 51
    • Analog front-ends must be designed with care Effect of imperfections on transmitted symbols Imperfection Any difference with ideal characteristic will degrade RF signal generation and… make signal demodulation more difficult.Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 52
    • Part V 5 – Research at Alcatel Lucent Chair in Flexible Radio @ SupélecSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 53
    • « Small cells » as a solution to densification Current mobile networks cannot follow customer bandwidth requirements… need for new network solutions•  Many small, low-cost, low-power BSs (50 to 150 meter range) as additional capacity/ coverage layer under a macro cell deployment•  Use existing backhaul infrastructure•  Collocated with existing street furniture (in-street cabinets/telephone booth, lamp posts, etc.) ➜ no cell site acquisition•  Self-organizing/maintaining (plug & play) ➜ no planningSoftware Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 54
    • Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 55
    • Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 56
    • Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 57
    • Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 58
    • Future of mobile networks – ALU Chaire @ Supélec We dream to have… The challenges we have to face…Software Defined Radio: Enjeux et perspectives – Sylvain AZARIAN et Jonathan PISANE 59