SDARS Receiver SDARS Receiver Front-EndFront-End

(Design Review)(Design Review)Albert KuliczAlbert Kulicz

Greg LandgrenGreg Landgren

Advisor: Prasad ShastryAdvisor: Prasad Shastry

OutlineOutline

OverviewOverview GoalsGoals Tasks for SemesterTasks for Semester AntennaAntenna LNA NetworkLNA Network FabricationFabrication Tentative ScheduleTentative Schedule

What is SDARS?What is SDARS?

This project involves designs, simulations, fabrication, This project involves designs, simulations, fabrication, and testing of a patch antenna and low-noise amplifier and testing of a patch antenna and low-noise amplifier (LNA) to receive SDARS signals by means of SIRIUS (LNA) to receive SDARS signals by means of SIRIUS receiver. receiver.

The inclusion of the entire active antenna (passive The inclusion of the entire active antenna (passive antenna + impedance matching network + LNA) will antenna + impedance matching network + LNA) will be designed to minimize physical size, while be designed to minimize physical size, while producing the best quality of signal.producing the best quality of signal.

System Block DiagramSystem Block Diagram

Passive Antenna

Low Noise Cascaded Amplifier Network

Impedance Matching Network

Active Antenna on PCB

F1 F2

G1 G2

SIRIUS Radio Receiver

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

Antenna GoalsAntenna Goals

Receive signals in the frequency band Receive signals in the frequency band from 2.32 GHz to 2.3325 GHz (BW of from 2.32 GHz to 2.3325 GHz (BW of 12.5 MHz)12.5 MHz)

LLeft eft HHand and CCircular ircular PPolarization olarization (LHCP)(LHCP)

Match in impedance to LNA network Match in impedance to LNA network

(~50 Ohms)(~50 Ohms)

Probe Feed – Placement will determine Probe Feed – Placement will determine polarization and impedance match polarization and impedance match

LNA GoalsLNA Goals

Noise factor shall be <= 1dBNoise factor shall be <= 1dB

NF = FNF = F1 1 + (+ (FF2 2 -1)/G-1)/G1 1 + (F+ (F33-1)/(G-1)/(G11*G*G22 ))++ . . . . . .

Total gain shall be -> 40~50 dBTotal gain shall be -> 40~50 dBGGtotaltotal = = G G11 + G+ G2 2 + . . .+ . . .

Tasks for SemesterTasks for Semester Complete EM simulations with Momentum and Complete EM simulations with Momentum and

optimize antenna design (Feb) optimize antenna design (Feb) Test LNA evaluation boards with NA (Feb)Test LNA evaluation boards with NA (Feb) Design Impedance Matching for the LNA network Design Impedance Matching for the LNA network

(Feb)(Feb) Simulate entire active antenna in Agilent ADS Simulate entire active antenna in Agilent ADS

(March)(March) Design Bias Circuitry for the LNAs (March)Design Bias Circuitry for the LNAs (March) Outsource Fabrication of Substrates (April)Outsource Fabrication of Substrates (April) Test Fabricated Antenna and LNA substrates (May)Test Fabricated Antenna and LNA substrates (May) Test complete systems active antenna board with Test complete systems active antenna board with

Sirius Receiver (May)Sirius Receiver (May)

3D Passive Antenna 3D Passive Antenna ModelModel

Antenna Dimension Antenna Dimension EquationsEquations

(L=W for square patch)(L=W for square patch) Initial length L = c/(2fo* Initial length L = c/(2fo* εεr^(1/2))r^(1/2))

εεeff= (eff= (εεr+1)/2 + (r+1)/2 + (εεr-1)/2*[1+12(h/L))^(-r-1)/2*[1+12(h/L))^(-1/2)1/2)

Fringe factor, Fringe factor, ΔΔL=0.412 h (ε eff + 0.3)L=0.412 h (ε eff + 0.3)( W/h + 0.264) / ( (ε eff - 0.258)(W/h + ( W/h + 0.264) / ( (ε eff - 0.258)(W/h + 0.8))0.8))

New length L = c/(2fo* New length L = c/(2fo* εεeff^(1/2)) - 2eff^(1/2)) - 2ΔΔLL repeat iterative process repeat iterative process 3.69cm x 3.69 cm 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 PCAAD (design for 2.326ghz)2.326ghz)

EM EM SimulationSimulation / / OptimizationOptimization

Agilent ADS - Patch Antenna S11

Patch Antenna – Top Patch Antenna – Top ViewView

Probe location: [x] 2.6372 cm x [y] 2.6372 cm (0.509 cm from center)

EM Simulation / EM Simulation / OptimizationOptimization

Agilent ADS - Patch Antenna S11

Impedance = Zo*(0.978-j0.001)

Antenna – Dissected Side Antenna – Dissected Side ViewView

Probe Feed: copper wire diameter – 0.15 cmProbe hole – 0.165 cm

Antenna - Bottom View Antenna - Bottom View (LNA network)(LNA network)

LNA schematicsLNA schematics

LNA experimental GainLNA experimental GainPowered by Sirius ReceiverPowered by Sirius Receiver

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

FabricationFabrication

Microcircuits, Inc.Microcircuits, Inc. Using Gerber files for both antenna and Using Gerber files for both antenna and

LNA layoutsLNA layouts

CAMtek, Inc.CAMtek, Inc. SolderingSoldering

Tentative ScheduleTentative Schedule

Finalize Antenna and LNA layout and Finalize Antenna and LNA layout and send Gerber file to Microcircuits (Mar.9)send Gerber file to Microcircuits (Mar.9)

Test fabricated Antenna performance Test fabricated Antenna performance (March)(March)

Send fabricated LNA substrate to CAMtek Send fabricated LNA substrate to CAMtek for soldering (March)for soldering (March)

Assembly of completed boards, solder Assembly of completed boards, solder probe, mount to a Plexiglas or plastic probe, mount to a Plexiglas or plastic encasing (April)encasing (April)

ConclusionConclusion

Finalized patch antenna dimensions Finalized patch antenna dimensions and probe locationand probe location

LNA network gain will not meet LNA network gain will not meet proposed goal, but will suffice for our proposed goal, but will suffice for our purposespurposes

Simulations show respectable return Simulations show respectable return loss at desired bandwidth loss at desired bandwidth

Fabrication and Assembly to be Fabrication and Assembly to be completed completed

ReferencesReferences[1] Zomchek, Greg and Zeliasz, Erik. “SDARS Front-End

Receiver: Senior Capstone ProjectReport.” 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 Wileyand Sons, Inc., 2005, pp.811-882[4] Pozar, David M. and Schaubert, Daniel H. “A Review of

Bandwidth EnhancementTechniques for Microstrip Antennas,” in Microstrip Antennas:

the analysis and design ofmicrostrip antennas and arrays Institute of Electrical and

Electronics Engineers, Inc., 1995,pp.157-165