ECE758858

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ECE758/858

• Communications Systems

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RF Circuit Design

• Importance
• Explosive growth in wireless communications
  demand
• GPS (Global Positioning System)
• 1227.6Mhz
• Computer Engineering
• Bus systems (exceeding 600Mhz)
• Memory
• CPU

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Lumped gt Distributed
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I V Vary Spatially over Component Size
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Frequency Spectrum

• Radio Frequency (RF)
• AM FM Radio
• Television
• Older wireless phones
• GPS
• Micro Wave (MW)
• Radar
• Remote Sensing
• Long Haul Point-to-Point Communications

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Frequency Spectrum

• Radio Frequency
• 300MHz to 3GHz
• 1 meter to 10 centimeters wavelength in air
• Micro Wave
• 8GHz to 40GHz
• 3.75 centimeters to 7.5 millimeter
• wavelength in air

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Distributed Parameter RF Design
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Implementation Schematic
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(No Transcript)
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Implementation Circuit Board
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(No Transcript)
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Laboratory Component

• Basic Lab
• Comprised of structured laboratory work to allow
  the student to become proficient in RF design and
  measurement
• Project
• Student Driven (Teams encouraged)
• Topic list to be given
• Approximately 7 Weeks in length
• Formal Report and Presentation Required

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Possible Project Topics

• Filter Design and Characterization
• FM Receiver Construction and Evaluation
• Frequency Shift Keying
• Modulator (One group)
• Demodulator (One group)
• Down Converter Design and Construction
• RF Amplifier Design and Construction
• DDS Reciever

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Components at RF

• What happens to components at high RF frequencies?

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TEM ModeTraverse Electromagnetic Mode
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RF Behavior of Passive Components
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Impedance Chart
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Resistor
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Resistor Model at High Frequency
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Resistor at RF
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Current Distribution for various frequencies
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Resistor Impedance Characteristic
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Capacitor High Frequency Model
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Capacitor Impedance Characteristic
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Capacitor Impedance Characteristic
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Equivalent Circuit Models