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
Top Related