Radiofrequency Electronic Systems (2019-2020)

Radiofrequency Electronic Systems
 (2019-2020)
 Instructors:

 Prof. Pasquale Tommasino

 Prof. Stefano Pisa

 lessons timetable

- Monday 12.00-14.00 classroom 6

- Wednesday 12.00-14.00 classroom 6

- Thursday 10.00-12.00 classroom 6

- Thursday 12.00-14.00 classroom 6

 9 CFU - 12 weeks (≈ 90 hours)

 1

TEACHING
 is not

 BUT

 FILLING LIGHTING
 a Bucket a Fire

 Ask questions, stop me

I like when this happens for at least two reasons.

First, one of the key things a Professor want to happen in
teaching is to activate the students' curiosity. When students
ask questions means that they're really engaged with the
material.

Second, when someone asks a question that's very
challenging, it's often a great opportunity to try to make a
particularly difficult problem clearer.

 2

How will a professor react when asked a question
 he can't answer?

 Bad professor: dodges the question or becomes
 angry.

Mediocre professor: promises to answer the question
 next class and never does.

Good professor: asks the class if anyone else knows;
 returns in the next class with an answer.

 RF/microwave Systems
 Denominations Frequency Interval GHz (109 Hz)
 HF 0.003 - 0.030
 VHF 0.030 - 0.300
 P (Previous) UHF 0.300 - 1.000
 L (Long) Band 1.0 - 2.0
 S (Short) Band 2.0 - 4.0
 C (Compromise) Band 4.0 - 8.0
 X (Cross*) Band 8.0 - 12.0
 Ku ( Under K) Band 12.0 - 18.0
 K Band 18.0 - 26.5
 Ka (Above K) Band Ka 26.5 - 40.0
 Q Band 40.0 - 50.0
 V Band 50.0 - 75.00
 millimeter 40.0 - 300.0
 Terahertz > 300.0
 *Used in WW II for fire control, X for cross (as in crosshair).

 3

Discrete Component Circuits
 PDIP (Plastic Dual Inline Package)

 SMD (Surface-Mounted Device)

 Digital TV Transmitter
 United States

In Europe Digital Video Broadcast - Terrestrial (DVB-T)
Frequency division multiplexing with orthogonal codes (COFDM)
with 16-QAM or 64-QAM. DVB-S (satellite)

 4

DVB-S Receiver

(DVB-S) Uplink 14-14.5 GHz Downlink 10.95 – 12.75 GHz (500 MHz)
RHCP (Right-Hand Circular Polarization) and LHCP polarizations

 Terrestrial Receiver-Transmitter
 (TX/RX) System
 (analog signal 2 -13 GHz)
 Local Oscilaltor

 Frequency Transmitter
 Modulator Antenna
 mixer
 Base-Band Amplifier Power
 signal Amplifier

 Local Oscillator
 Local Oscilaltor Intermediate
 Frequency
 Amplifier Base-Band
 Signal
 Receiving Frequency
 Antenna Demodulator
 mixer

 5

Satellite Transponder
 (digital signals)
 Local fOL
 Oscillator

 Receiver Intermediate
 Antenna Low-Noise Frequency Amplifier
 Amplifier

 fIN QPSK
 Demodulator
 mixer

 Local Oscilaltor
 fOL1  fIN Power Amplifier

 QPSK Transmitting
 Rigenerator Antenna
 Modulator

 Doppler Radar
 Transmitting
 and
 Receiving
 Antenna
 Microwave Directional Coupler Body
 Source 3 dB Hybrid
Continous Wave
 (DRO)

 v(t) = V1 sen(1t) v(t) = V0 sen(0t)

 mixer

 vIF(t)

 Filter

 Doppler
 Vout(t) Frequency

 6

FMCW Radar

 0 
 = · ·
 2 

 Course Outline
• INTRODUCTION: Examples of telecommunication and
 radar systems, example of a project.

• RF OSCILLATORS: resonant circuits, factors of
 merit and loss, examples of RLC networks, frequency
 stability coefficient, quartz as a circuit element,
 phase noise; Colpitts and quartz oscillators. Negative
 resistance oscillators: steady state and triggering
 conditions, dielectric resonator oscillators, ceramic
 resonator oscillators.

 7

• RF AMPLIFIERS: stability, stability circumferences,
 Rollet factor, Nyquist method, transducer gain
 evaluation. Amplifiers for maximum gain: design based
 on unconditionally stable transistors, lumped-
 distributed matching networks implementation, design
 based on conditionally stable transistors, design of
 stabilization networks, design in the stable region.
 Noise Figure, Low noise amplifiers, design for the
 minimum noise figure. Power amplifiers, parameters
 and classes of amplifiers, design of class A power
 amplifiers. Design starting from non-linear models and
 from load-pull measurements.

• RF MIXER: characteristic parameters of Mixer,
 mixers with transistors: BJT, JFET. Mixer with
 diodes: non-linear model of the schottky diode, causes
 and patterns of noise in diodes, single diode mixer,
 balanced mixers.

• RF FILTERS: Design of RF filters based on the “low-
 pass prototype” method, design of low-pass high-pass
 and band-pass filters with lumped elements. Low pass
 filter realization with microstrips.

 8

• PLL (phase-locked loop) : operating principle,
 response to a phase and frequency error, stability,
 design of a PLL.

 • Modulators and Demodulators: AM Modulators and
 demodulators, SSB, frequency modulators, IF
 amplifier and gain control.

 • CAD (computer aided design) Laboratory: Examples
 with Microwave Office, of all the described
 circuits.

 The following CAD examples
 will be presented:
1. design of matching networks and RLC circuits;

2. design of oscillators (Colpitts, Quartz, Ceramic);

3. design of amplifiers (maximum gain, and power
amplifiers);

4. design of filters with lumped and distributed
elements.

 9

RF ELECTRONIC SYSTEMS
 HF VHF-UHF MICROWAVES

OSCILLATOR COLPITTS COLPITTS CRO
 QUARTZ CRO DRO
AMPLIFIERS
High Gain Elettronics II Elettronics II REACTIVE
 MATCHING
Low Noise Elettronics II Elettronics II REACTIVE
 MATCHING
High Power HF VHF UHF REACTIVE
 TRASFORMER TRASFORMER MATCHING

MIXER Schottky Diodes Schottky Diodes SCHOTTKY DIODES
 Diplexer Diplexer 180° Hybrid
 TRANSISTORS TRANSISTORS TRANSISTORS
FILTERS LUMPED LUMPED (SMD) MICROSTRIP
MODULATOR, DEMODULATOR
CAD EXERCICES (MICROWAVE OFFICE) ALL THE DESCRIBED CIRCUITS

 Course Material
 Textbook:
 • Lecture notes available on the web site:
 http://mwl.diet.uniroma1.it/people/pisa/RFELSYS.html

 Recommended textbooks:
 • 1. Kikkert_RF_Electronics_Course
 • 2. David M. Pozar, Microwave Engineering, Fourth Edition
 • 3. H.L. Krauss et al., Solid State Radio Engineering
 • 4. Guillermo Gonzalez, Microwave Transistor Amplifiers

 Web sites:
 • 1. https://www.rf-microwave.com/en/home/ (italian supplier of RF
 components)
 • 2. http://www.awrcorp.com/products/microwave-office

 10

11

awrde_v14_04_9307_2_64bit

 12

Grading
 Your course grade will be determined as follows:

 35% : Oral exam on one topic covered by
 Prof. Tommasino lectures

 35% : Oral exam on one topic covered by
 Prof. Pisa lectures

 30% : MWO project work

 Design of RF Circuits
1) Design Specifications

2) Dimensioning (Analytical, Smith's Chart, etc.)

3) Layout (CAD)

4) Optimization (CAD)

5) Prototype Realization (Milling Machine, Chemical
 Etching)

6) Prototype Measurement

 13

Filter design Specifications
 • Low Pass Filter

 • maximally flat

 • Cut-off Frequency, fC = 5.5 GHz

 • Cut-off Attenuation, Ac= 3dB

 • Out of band Attenuation = 10 dB at 7 GHz

 Dimensioning (Ideal)
 low pass prototype method
Filter Elements N = 5
g1=0.618, g2=1.618, g3=2, g4=1.618, g5=0.618

 PORT IND IND PORT
 P=1 ID=L1 ID=L2 P=2
 Z=50 Ohm L=2.341 nH L=2.341 nH Z=50 Ohm

 CAP CAP CAP
 ID=C1 ID=C2 ID=C3
 C=0.358 pF C=1.157 pF C=0.358 pF

 14

Dimensioning Results

 1 Risposta in Ampiezza
 0
 5.5 GHz
 -3.02

 5.5 GHz
 -10
 -2.93

 DB(|S[2,1]|)
 -20
 1 Binomiale

 DB(|S[2,1]|)
 2 Chebychev
 -30
 4 5 6 7 7.5
 Frequency (GHz)

 Physical Dimensioning

 MLIN MSTEP MLIN MSTEP MLIN MSTEP MLIN MSTEP MLIN MSTEP MLIN MSTEP MLIN PORT
PORT ID=TL7 ID=TL8 ID=TL1 ID=TL9 ID=TL2 ID=TL10 ID=TL3 ID=TL11 ID=TL4 ID=TL12 ID=TL5 ID=TL13 ID=TL6 P=2
P=1 W=w50 mm W1=w50 mm W=w15 mm W1=w15 mm W=w75 mm W1=w75 mm W=w15 mm W1=w15 mm W=w75 mm W1=w75 mm W=w15 mm W1=w15 mm W=w50 mm Z=50 Ohm
Z=50 Ohm L=20 mm W2=w15 mm L=0.910 mm W2=w75 mm L=5.872 mm W2=w15 mm L=2.947 mm W2=w75 mm L=5.872 mm W2=w15 mm L=0.910 mm W2=w50 mm L=20 mm

 w50=1.161
 w15=5.844 MSUB
 MLIN MSTEP MLIN Er=3.38
 w75=0.544 H=0.508 mm
 ID=TL1 ID=TL9 ID=TL2
 w15=5.844 W=w15 mm W1=w15 mm W=w75 mm T=0.035 mm
 Rho=0.7
 w75=0.544 L=0.910 mm W2=w75 mm L=5.872 mm Tand=0.0027
 ErNom=3.38
 Name=RO1

 15

Physical Dimensioning Results
 Realizzazione Fisica
 0
 5.12 GHz
 -3

 -5 5.5 GHz
 -4.72

 DB(|S[2,1]|)
 -10 5 Realizzazione Fisica

 DB(|S[2,1]|)
 1 Binomiale
 -15
 4 5 6 7 7.5
 Frequency (GHz)

because of the steps, there is a noticeable deviation from the ideal behavior

 CAD Optimization
 Goal: Attenuation greater than 10 dB at 7 GHz
 Variables: Line length
 Optimization methods: Random + Gradient
 Realizzazione Fisica
 0
 5.5 GHz
 -2.99

 -5

 DB(|S[2,1]|)
 1 Binomiale
 -10
 DB(|S[2,1]|) 7 GHz
 6 Layout -10.4

 -15
 4 5 6 7 7.5
 Frequency (GHz)

 16

Layout

 17