Ultra-Wide Band FMCW Receiver Design for Airborne Applications

1. Ultra-Wide Band FMCW Receiver Design for Airborne Applications By: Jay McDaniel

2. Scope • Project Description • FMCW Review • Challenges for Design of Airborne Applications • UWB Design Challenges • 2-18GHz FMCW Radar Design • Integrated Layout Design • Need for UWB Radar • Questions

3. Project Description Goals • Design and integrated layout of FMCW radar • Challenges associated with UWB designs • Challenges associated with airborne applications Deliverables • Paper design of a 2-18GHz FMCW radar • Integrated layout design ready for fabrication • Project Report

4. Frequency Modulated Continuous Wave • T = Repetition Period Bandwidth(B) = f2-f1 • Chirp Rate(k) = B/T Resolution(δR) = c/(2*B) • Beat Frequency(Δf) = (2*R*k)/c c = 3x10^8m/s (free-space)

5. Airborne Application Design Challenges

6. Airborne Application Design Challenges • Design Considerations • Altitude Variations • Look Angle Variations • Backscatter Coefficient (σo) • Range Resolution (ΔR/2sin(θ)) • Antenna Gain, Pattern • Radar Range Equation Nadir Case Off-Nadir Case

7. UWB Design Challenges • Design Considerations • Expensive/Limited Hardware Options • Connectorized vs. Surface Mount Components • Frequency Dependency • Antennas • Gain and Pattern variations • Amplifiers, Mixer, and Attenuators • Gain Variations • Gain Equalizer (Active or Passive) • Board Layout • Technology: Microstrip, Stripline, CPWG

8. 2-18GHz FMCW Receiver Design

9. 2-18GHz FMCW Receiver Design • Maximum Expected Signal = -53.21dBm • Minimum Expected Signal = -73.21dBm • Input Saturation Power = -43dBm • MDS = -119dBm • Receiver Gain ≈ 55dB • ADC Dynamic Range is from 10dBm to -66dBm

10. Integrated Layout Design

11. Integrated Layout Design

12. Integrated Layout Design

13. Why UWB? • Remember, the range resolution is c/2B. Therefore, the larger the bandwidth the finer resolution you can achieve.

14. Questions???