SDARS Receiver Front-End (Design Review) Albert Kulicz Greg Landgren Advisor: Prasad Shastry

Outline Overview Goals Tasks for Semester Antenna LNA Network Fabrication Tentative Schedule

What is SDARS? This project involves designs, simulations, fabrication, and testing of a patch antenna and low-noise amplifier (LNA) to receive SDARS signals by means of SIRIUS receiver. The inclusion of the entire active antenna (passive antenna + impedance matching network + LNA) will be designed to minimize physical size, while producing the best quality of signal.

System Block Diagram Incoming Circularly Polarized Satellite Signal (-105 to -95)dbm

Antenna Goals Receive signals in the frequency band from 2.32 GHz to 2.3325 GHz (BW of 12.5 MHz) Left Hand Circular Polarization (LHCP) Match in impedance to LNA network (~50 Ohms) Probe Feed – Placement will determine polarization and impedance match

LNA Goals Noise factor shall be <= 1dB NF = F1 + (F2 -1)/G1 + (F3-1)/(G1*G2 )+ . . . Total gain shall be -> 40~50 dB Gtotal = G1 + G2 + . . .

Tasks for Semester Complete EM simulations with Momentum and optimize antenna design (Feb) Test LNA evaluation boards with NA (Feb) Design Impedance Matching for the LNA network (Feb) Simulate entire active antenna in Agilent ADS (March) Design Bias Circuitry for the LNAs (March) Outsource Fabrication of Substrates (April) Test Fabricated Antenna and LNA substrates (May) Test complete systems active antenna board with Sirius Receiver (May)

3D Passive Antenna Model

Antenna Dimension Equations (L=W for square patch) Initial length L = c/(2fo* εr^(1/2)) εeff= (εr+1)/2 + (εr-1)/2*[1+12(h/L))^(-1/2) Fringe factor, ΔL=0.412 h (ε eff + 0.3)( W/h + 0.264) / ( (ε eff - 0.258)(W/h + 0.8)) New length L = c/(2fo* εeff^(1/2)) - 2ΔL repeat iterative process 3.69cm x 3.69 cm [1] Balanis, Constantine A, “Microstrip Antennas,” in Antenna Theory, 3rd ed. John Wiley and Sons, Inc., 2005, pp. 811-882

PCAAD (design for 2.326ghz)

EM Simulation / Optimization Agilent ADS - Patch Antenna S11

Patch Antenna – Top View Probe location: [x] 2.6372 cm x [y] 2.6372 cm (0.509 cm from center)

EM Simulation / Optimization Agilent ADS - Patch Antenna S11 Impedance = Zo*(0.978-j0.001)

Antenna – Dissected Side View Probe Feed: copper wire diameter – 0.15 cm Probe hole – 0.165 cm

Antenna - Bottom View (LNA network)

LNA schematics

Powered by Sirius Receiver LNA experimental Gain Powered by Sirius Receiver

Entire System (Passive Antenna & LNA) S11 (return loss) Entire System (Passive Antenna & LNA)

Fabrication Microcircuits, Inc. CAMtek, Inc. Using Gerber files for both antenna and LNA layouts CAMtek, Inc. Soldering Room for error, so we will have to gather 2 antennas from Microcircuits (just in case).

Tentative Schedule Finalize Antenna and LNA layout and send Gerber file to Microcircuits (Mar.9) Test fabricated Antenna performance (March) Send fabricated LNA substrate to CAMtek for soldering (March) Assembly of completed boards, solder probe, mount to a Plexiglas or plastic encasing (April)

Conclusion Finalized patch antenna dimensions and probe location LNA network gain will not meet proposed goal, but will suffice for our purposes Simulations show respectable return loss at desired bandwidth Fabrication and Assembly to be completed

References Report.” Bradley University, Spring, 2001. [1] Zomchek, Greg and Zeliasz, Erik. “SDARS Front-End Receiver: Senior Capstone Project Report.” Bradley University, Spring, 2001. [2] Lockwood, Kevin. “SDARS Front-End Receiver: Senior Capstone Project Report.” Bradley University, Spring, 2011. [3] Balanis, Constantine A., “Microstrip Antennas,” in Antenna Theory, 3rd ed. John Wiley and Sons, Inc., 2005, pp.811-882 [4] Pozar, David M. and Schaubert, Daniel H. “A Review of Bandwidth Enhancement Techniques for Microstrip Antennas,” in Microstrip Antennas: the analysis and design of microstrip antennas and arrays Institute of Electrical and Electronics Engineers, Inc., 1995, pp.157-165