1 / 34

Ultra-Wideband Research and Implementation

Ultra-Wideband Research and Implementation. By Jarrod Cook and Nathan Gove Advisors: Dr. Brian Huggins Dr. In Soo Ahn Dr. Prasad Shastry. Presentation Outline. Introduction Overview Project Summary Spectrum Overview Modulation Project Issues Time Constraints Sampling Rates

nash
Download Presentation

Ultra-Wideband Research and Implementation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ultra-Wideband Research and Implementation By Jarrod Cook and Nathan Gove Advisors: Dr. Brian Huggins Dr. In Soo Ahn Dr. Prasad Shastry

  2. Presentation Outline • Introduction • Overview • Project Summary • Spectrum Overview • Modulation • Project Issues • Time Constraints • Sampling Rates • ADC / DAC issue • Project Schedule • Website Updates • Project Milestones • Model • Block Diagram • Frame Synchronization • Integration with CCS and DSPs • Hardware • 2/3 of Hardware Received • LO Tested • Future Work • Questions?

  3. Introduction to UWB • Ultra-wideband technology is a wireless transmission technique approved for unlicensed use in 2002 under the FCC Part 15 • Ideal for portable multimedia devices because of its inherent low power consumption and high bit rates

  4. Why Research UWB? • UWB is likely to revolutionize the consumer electronic market in the near future. • Wireless USB devices • Wireless communication for High-Definition devices • UWB has the power to eliminate the majority of wires to and from multimedia devices

  5. Overview • Brief History • IEEE 802.15.3a • ECMA 368 and 369 • Consumer Electronics Demand • High data-rate wireless transmissions • Low power consumption for portable devices • UWB allows data rates equivalent to USB 2.0 (480 Mb/s)

  6. Project Summary • The goal of this project is to complete a scaled-down version of a UWB transceiver pair. • Specifically, we are focusing on the following: • Understanding the theory • Simulink modeling • DSP implementation • RF transceiver hardware • Testing

  7. UWB Spectrum Overview • Power spectral density • -41.3 dBm/MHz • FCC part 15 limit • Frequency Range • 3.1 to 10.6 GHz • Sub-bands

  8. Modulation • QPSK or 4-QAM • Gray Coded Mapping • Symbols • Used for data rates from80 to 200 Mb/s • I & Q • 16-QAM or DCM • Used for data rates from320 Mb/s to 480 Mb/s

  9. OFDM

  10. OFDM • Benefits • Resistance to multi-path fading • Spectrum • Full ECMA standardized UWB spectrum • Scaled-down project spectrum

  11. Project Issues • Due to Time Constraints • Power Limitation • Must be overlooked for this initial project • Output of quadrature modulators exceed limitations • Transmission Bandwidth / Data Rate • ACD and DAC are not sufficient • Audio Development Kit • UWB Coding Specifications 20% Met • Pseudo-random code / spreading / time interleaving • Forward Error Correcting • Data frame will not include full preambles / headers

  12. Project Issues • Sampling Times • Simulink requires information at equal times • Must be very careful when changing sampling rates • ADC / DAC Issues • DAC • Need to Transmit In Phase and Quadrature Phase Components • DACs can only output real numbers • Two DACs are required • Board only has one DAC • Daughter Boards Required • Both • With faster converters, wider bandwidths possible

  13. Overall Tx / Rx Block Diagram

  14. Simulink Model • Model • Frame Synchronization • Preamble Complete

  15. Updated Project Schedule

  16. Updates on Project Website • UWB Website Updates

  17. DSP Platforms received C6416 DSK Progress

  18. Integration of Simulink with CCS • To use the DSP boards, all that has to be added to the model is the “C6416DSK” block. • Simulink has a blockset for this model • Allows use of ADC and DAC • LEDs • DIP Switches • Software Reset • Running the model automatically launches CCS which converts the model to C-code and uploads it.

  19. Simple DSP Test with CCS • DSP Platform Hardware • Tested with Simulink and Code Composer Studio (CCS) • Used a FIR Filter for a quick test

  20. Simple Test Cont. • Once we figured out how to successfully upload models, we did a quick FIR filter model to test the model. • Sampling rate: 32 kHz • Passband: 0 to 5 kHz • Stopband: 6 kHz • Results • Did a quick frequency sweep of the filter through the DSP to visually confirm the DSP was working

  21. RF Hardware • The RF local oscillator and direct quadrature modulator have arrived.

  22. Local Oscillator Test • The oscillator was tested on the spectrum analyzer to verify that it met the specifications stated in the data sheet. • Data sheet specs: • Tunable from 3.35 to 3.55 GHz • Typical power output: 4.7 dBm (1.5 minimum) • Current draw: 41 mA • Harmonic levels: -7 and -16 dBc

  23. Local Oscillator • Tests performed: • Output frequency vs. tuning voltage • Output power vs. tuning voltage • Harmonic power levels • The frequency vs. tuning voltage matched up with the data sheet nicely • The output power was much lower than the specs (on the order of 0.5 to 1.2 dBm) • Determined the loss of the coax, DC block, and connectors to be around 1 dB. Therefore, results are more normal • Harmonic Power levels matched data sheet specs

  24. Local Oscillator

  25. Local Oscillator

  26. Local Oscillator

  27. Local Oscillator

  28. Local Oscillator

  29. Local Oscillator

  30. Future hardware testing • Quadrature Modulator • Quadrature De-Modulator • Interconnecting all the hardware for testing • Transmission lines as channel before wireless • Signal leaves DSP on a 3.5mm audio jack, and must be received by the modulator with an SMA connector. • Impedance mismatches?

  31. Hardware Connections

  32. Future Work Previous To Do List Current To Do List • Baseband processor • Increase complexity • Research UWB channels (no longer implementing) • Determine maximum feasible sampling rate • Purchase DSP board • Implement synchronous coherent detection for receiver • RF Transmitter • Find a suitable quadrature modulator • Determine and purchase hardware • Model and Design (no longer implementing) • Fabricate hardware (no longer implementing) • Antenna research (no longer implementing) • RF Receiver • LNA Design and modeling (N. L. I.) • Determine and purchase hardware • Fabricate hardware (N. L. I.) • Testing • Transmitter • Implement Daughterboard DACs and ADCs • Receiver • Complete Frame Synchronization • Pulse on Frame Start • Frame Alignment • Implement Carrier Synchronization • Using the Pilot Signals correct for the phase error. • Testing • System Integration • Full system testing • Bandwidth measurements • Bit Error Rates • Other common communication systems measurements.

  33. Questions ? ? U W B Standards

More Related