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Overview and Background Operates in Ku Band 12-18GHz Design is based on Bell Satellite Receiver As of 2010 Bell TV had over 2 million satellite customers DBS Receiver http://sonamjourno.blogspot.ca/2012_09_01_archive.html
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DBS Receiver System Presented By: Sarah Scharf, Pierre
Desjardins,GuiPing Zhang, Peter Eseraigbo Supervisor: Prof. Barry
Syrett Overview and Background
Operates in Ku Band 12-18GHz Design is based on Bell Satellite
Receiver As of 2010 Bell TV had over 2 million satellitecustomers
DBS Receiver Motivation Receivers are used in all communication
systems
Cellular communication Military radar and navigations systems
Television broadcasting Opportunity to develop design skills
whichare directly applicable to the communicationindustry
Significance of Project
Opportunity to create a basic receiver designand look for possible
improvementsuggestions This receiver design can be used by
futurestudents to investigate more efficient andcheaper receiver
design options Satellite Receiver System
Diagram of our system: Project Management Each individual was
assigned a component toresearch and design Conducted weekly group
meetings Met with supervisor on an as-needed basis Communicated
both verbally and through frequently Roles and
Responsibilities
Pierre: Antenna system and band-pass filter Reflector dish and
Antenna feed Name Expected Results Antenna Gain 34.5dBi 32.77dBi
3dB Beamwidth 3.5deg 4deg 10dB Beamwidth 5.5deg 6deg Roles and
Responsibilities (cont)
Band-Pass Filter (12.25GHz GHz) Roles and Responsibilities
(cont)
Gui: the two stage LNA is designed withmicrostrip transmission line
and usedpseudomorphic high-electron- mobility transistors. The
designedgain is 20 dB and noise figure is lowerthan 2 dB. Design
LNA Methods and Techniques
Using ADS software; Designed with Microstrip transmissionlines
instead of lump elements. Started from Stage one with lowernoise
figure and then second stagewith high gain. Optimized gain, noise
figure andstability in ADS environment. Challenges and
Solution
How to maintain the circuit stability at themeantime achieving
enough gain; Solution is by make a compromise betweengain and
stability The minimum specified gain for this LNA is 20 dB Design
Results Noise figure and stability
It only has lower than 2 dB noise figure. And the circuit is stable
Design Results-Final Layout
This two stage LNA is expected to producethe required gain Roles
and Responsibilities (cont)
Peter: GHz Dielectric ResonatorOscillator (DRO) Primary purpose of
the oscillator is to generateand maintain aneeded waveform at a
constant amplitude and specific frequency Antenna IF = LO - RF
MIXER IF Filter Signal Processing IF RF LO BPF LNA OSCILLATOR RF =
12.5 GHz IF = 1.25 GHz LO = Local Oscillator IF = Intermediate
Frequency RF = Radio Frequency LO = GHz LO = GHz Advantages of
topology
Methods and Techniques Circuit Topology Topology uses a resonator
coupled to microstrip line, functioning as a high-Q bandstop filter
that couples a portion of the transistor output back to its input.
Advantages of topology Very high unloaded Q (Severalthousand)
lumped elements are limited to fewhundred Low phase noise (Better)
Good output power Excellent temperature stability ofmaterial they
are made from Matching Network Series Feedback DRO Circuit
Implementation In ADS
Simulation done using large signal simulator Harmonic Balance
Parallel ResonantCircuit withtransformer coupling Active Device
(BJT) Matching Network Circuit Shematic Series Feedback DRO
circuitin ADS Challenges and Solutions
Getting oscillator to oscillate Adding current pulse Achieving
desired oscillation frequency Investigating what circuit components
affectoscillator frequency. Trial and Error. Changing LC values and
re- simulating until oscillation frequency was achieved. Results
Roles and Responsibilities (cont)
Sarah: Active BJT Mixer Methods and Techniques BFU710 by NXP
selected as active mixer component Chosen mixer topology Roles and
Responsibilities (cont)
Challenges and Solutions I-V curve for BJT showing approximatebias
point Mixer starting point Roles and Responsibilities (cont)
Results and Discussion Approximate layout Output Spectrum: Output
voltage at 1.25 GHz Progress to Date Chosen and purchased active
components
Design using ADS and HFSS Simulation of design Design layouts
completed Send out layouts for manufacturing Next Steps Complete
and test individual printed circuits
Complete second iteration of design andmanufacture if necessary
Present final result in written report DBS Receiver Please stop by
our poster for further technicaldetails. References
-bell-tv-subscriber-spends-75-a-month/ ite_TV_Frequency_Bands.asp
98a6.pdf BLKG.html
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