progress report satellite digital audio radio service...

Satellite Digital Audio Radio

Service Front End Final Presentation

By: Keven Lockwood

Advisor: Dr. Prasad Shastry

1

Satellite Radio

2

Overview

• SDARS transmissions

• Functional description

• Goals

• Antenna design, specifications, and

measurements

• LNA design, specifications, and

measurements

• Conclusions

3

SDARS Transmissions

http://cegt201.bradley.edu/projects/proj2001/s

darsprj/funcdesc.html

4

System Description

5

Incoming

EM

signal

-105 dBm to -95 dBm39.5 dB to 49 dBLow gain 3 to 6 dB

Expanded Project Block Diagram

6

Transmission Polarization

7

Pictures from: Ulaby, Fawwaz T.

Fundamentals of Applied

Electromagnetics. 5th ed.

• Circular Polarization (CP) offers:

– The ability to receive in all planes.

– CP waves are better for penetrating and bending

around obstructions.

– The multipath effect is reduced.

– Signals are better at penetrating weather and foliage.

• CP measured by Axial Ratio

– Major axis / minor axis of the electric field

Linear Elliptical Circular

Project Goals

1) Design LP proximity coupled antenna

2) Design CP proximity coupled antenna

3) Fabricate the CP Antenna

4) CP Antenna measurements

5) Research and purchase low-noise amplifiers

6) Fabrication of LNA circuit

7) LNA measurements

8) Construct the active antenna (antenna plus LNA) and test with receiver

8

Antenna Specifications

• 2320 MHz to 2332.5 MHz

• 3 dBic gain

• VSWR 2:1

• LHCP Axial Ratio = 0 dB

9

Circularly Polarized Antenna

Design• Transmission line model

• Manual Tuning in Momentum

• L operating frequency

• W axial ratio (small effect)

• S Zimg

• Ws Zo

• Lo axial ratio (large effect)

• Substrate εr and thicknesses t and h preset

10

CP Antenna Design Cont.• Perturbations split modes, determine axial ratio

• Perturbed area derived from Quality Factor

• Lo moved to center

• Overall improved axial ratio

11

CP Antenna Simulations

12

2.15 2.20 2.25 2.30 2.35 2.40 2.452.10 2.50

-2.5

-2.0

-1.5

-1.0

-0.5

-3.0

0.0

Frequency

Ma

g.

[dB

]

Readout

m1

Readout

m2

S11

m1freq=dB(patch_mom..S(1,1))=-1.266

2.320GHz

m2freq=dB(patch_mom..S(1,1))=-1.265

2.332GHz

2.22 2.24 2.26 2.28 2.30 2.32 2.34 2.36 2.382.20 2.40

-60

-50

-40

-30

-20

-10

-70

0

freq, GHz

dB

(S(1

,1))

Readout

m4

Readout

m5

S11

m4freq=dB(S(1,1))=-19.380

2.320GHz

m5freq=dB(S(1,1))=-17.082

2.334GHz

• Return Loss

• Antenna patch length and width unchanged from initial LP design

Unmatched antenna Matched antenna

CP Antenna Simulations

13

freq (2.100GHz to 2.500GHz)

Readout

m3

S11

m3freq=patch_mom..S(1,1)=0.865 / -179.994impedance = Z0 * (0.072 - j5.248E-5)

2.326GHz

• Input impedance before matching (blue) and after (red)

CP Antenna Simulations

• Axial Ratio and Gain

14

Fabricated Antenna

15

Fab Antenna Measurements

• functions with receiver system

• Return loss measured (S11)

• Anechoic chamber experiment to be

complete

– Gain estimation

– Radiation pattern

– Axial Ratio

16

Fab Antenna Measurements

17

• Return loss (S11) simulated (left) and measured (right)

Fab Antenna Measurements

• Input impedance simulated (left) and measured (right)

18

freq (2.020GHz to 3.000GHz)

pro

xim

ity_

fed

_2

..S

(1,1

)

Readout

m12

m12freq=proximity_fed_2..S(1,1)=0.811 / -7.326impedance = Z0 * (6.997 - j4.237)

2.326GHz

LNA specifications

• 25.5 to 29.5 dB LNA gain – 2 amps cascaded: each with minimum 12.75 dB gain

• 28.5 to 32.5 dB total gain (LNA + antenna)

• 2320 MHz to 2332.5 MHz operation

• Zo = 50 Ω

• NF ≤ 0.9 dB

• HMC715LP3

– 2.1 to 2.9 GHz operation

– NF = advertises 0.9 dB, but is 0.86 on data sheet

– Gain = 19 dB

– 3 to 5 V supply

– Output P-1dB ≈ 18.5 dBm at 2326 MHz

19

Pictures taken from Hittite HMC715LP3E datasheet

LNA Block diagram

20

LNA Evaluation BoardHittite

HMC715LP3E

From antenna

Modular AmplifierMini-CircuitsZEL-1724LN

To Sirius Receiver

Gain = 19 dBNF = 0.9 dB

Gain = 20 dBNF = 1.5 dB

Blocking Capacitor

LNA Noise Figure Measurement

21

LNA Noise Figure Measurement

22

• Spectrum analyzer used– Pn1 dBm when noise source is off (top)

– Pn2 dBm when noise source is on (bottom)

• YdB = Pn2 dBm – Pn1 dBm

• Ft db = ENRdb – 10*log(Y-1)– ENR = Excess noise ratio of the source

• Ft = F1 + (F2 – 1)/G1

• Solve for F1 to get noise figure of the

LNA

• Ft dB is the noise figure of cascade

• Second stage noise factor

contribution is only 0.005

• Variance in measurements– Ft dB between 1.38 dB and 4.57 dB

LNA gain

• Measured using the network analyzer and

VeePro

• G = 19.2 dB @ Vs = +5V

• G = 17.9 dB @ Vs = +3V

• Slides 29 and 34 for graphs

23

Potential Improvements

• Observe impedance locus as a function of line inset to produce maximum coupling

• Decrease the length of the tuning stub and short the end with a via hole to increase bandwidth.

• Explore changes in patch length for better S11, after perturbations made

• Lengthen the tuning stub with a metallic strip or shorten to improve return loss

24

Conclusions

• A Proximity-coupled, perturbed patch antenna

• No time for LNA PCB design and integration, evaluation board used

for now

• Design of antenna and LNA was made modular, not integrated

• VSWR does not meet spec, yet signals are received

• LNA module pushes NF spec, yet signals are received

• Anechoic chamber experiment to be complete

25

Sources / Questions?

• [1] Kazuhiro Hirasawa, Misao Haneishi. Analysis, Design, and Measurement of Small

and Low-Profile Antennas. Artech House, Boston, London. Provided by Bradley

University. P. 59 and 71.

• [2] J.R. James, P.S. Hall, C. Wood. Edited by G. Millington, E.D.R. Shearman, J.R.

Wait. Microstrip Antenna Theory and Design. The Institute of Electrical Engineers,

London and New York. Peter Peregrinus Ltd., 1981. Provided by Bradley University.

• [3] Balanis, Constantine A. Antenna Theory: Analysis and Design. 2nd Ed. John Wiley

and Sons, Inc., 1997. pp. 760-762.

• [4] James R. James, Jim R. James, Institution of Electrical Engineers. Handbook of

Microstrip Antennas Vol. 2. Peter Peregrinus Ltd. 1989. pp. 228-231.

• [5] H. Iwasaki, H. Sawada, K. Kawabata. “A Circularly Polarized Microstrip Antenna

Using Singly-Fed Proximity Coupled Feed.” Institute of Electronics, Information and

Communication Engineers. September 1992. pp. 797-800.

26

Extra: Probe-fed Antenna S11

27

Measurements taken from Zombchek

LNA measurements: Vbias = 3V

HMC715LP3 gain (S21 mag dB), 2.32 GHz: 17.925 dB,

2.32625GHz: 17.956 dB. 2.3325GHz: 17.993 dB, 3V, 14mA

Measurements

taken using

VPro

28

LNA measurements: Vbias = 3V

S21 Phase. 2.32 GHZ: -99 degrees, 2.32625GHz: -94.841

degrees, 2.3325GHz: -90.553 degrees. 3V. 29

LNA measurements: Vbias = 3V

S11 magnitude dB. 3V. 2.32GHz: -10.159 dB, 2.32625GHz: -10.11

dB, 2.3325GHz: -10.145 dB.30

LNA measurements: Vbias = 3V

S12 mag dB. 2.32GHz: -31.246 dB, 2.32625GHz: -30.827 dB,

2.3325 GHz: -30.102 dB. 3V. 31

LNA measurements: Vbias = 3V

S22 mag dB. 2.32GHZ: -11.571 dB, 2.32625GHZ: -11.56 dB,

2.3325GHz: -11.582 dB. Vbias = 3V 32

LNA measurements: Vbias = 5V

S21 mag dB. 5V. 70.66mA. L: 19.288dB, C: 19.205, R: 19.245.

33

LNA measurements: Vbias = 5V

S21 phase. 5V. L:-88.856 degrees, C: -89.439 degrees, R: -90.147

degrees34

LNA measurements: Vbias = 5V

S11 mag dB. 5V. L: -9.974 dB, C: -9.995 dB, R: -9.984 dB.

35

LNA measurements: Vbias = 5V

S12 mag dB. 5V. L: -32.151 dB, C: -32.129 dB, R:-31.997 dB.

36

LNA measurements: Vbias = 5V

S22 mag dB. 5V. L: -11.627 dB, C: -11.574 dB, R: -11.55 dB.

37

LNA measurements: Vbias = 5V

S(1,1) and S(2,2) measured values

10.0734

0.319294 0.0223801 0.354151

9.213

0.3164 0.02475 0.26381

4.34

0

2

4

6

8

10

12

S(1,1) S(2,1) S(1,2) S(2,2)

(series 1) Hittite measurements, (series 2)

experimental measurements, (series 3) target values

lin

ear

mag

nit

ud

e

Series1

Series2

Series3

• Hittite specs match measurements.

• Ports are reasonably matched to 50 Ohms.

• Comparison of min gain spec in yellow. 38

-9.916184848

20.06352159

-33.00275955

-9.016230551

-9.995270503

19.28802142

-32.12849593

-11.57417492

12.74979459

-40

-30

-20

-10

0

10

20

30

S(1,1) S(2,1) S(1,2) S(2,2)

mag

nit

ud

e (

dB

)

(series 1) Hittite measurements, (series 2) experimental measurements, (series 3) target values

S-parameter measured values with 5V bias

Series1

Series2

Series3

S-Parameter measured values with 5V bias

Initial Calculations and PCAAD

6.0

39

Linearly Polarized Antenna

• Length of patch: 1538 Mil

• Width of patch: 1592 Mil

• length of feed line: 814 Mil

• Width of feed line: 89.25 Mil (50 Ohms)

• Red = upper layer

• Yellow = lower layer 40

L.P. Antenna 3D view

41

Proximity Coupled Patch:

PCAAD 6.0

• 3.9065 cm = 1538 Mil

• 4.0437 cm = 1592 Mil

42

L.P. Antenna Measurements: Zin at

port 1– Measurements using Momentum

– Center frequency = 2.32625 GHz

2.25 2.30 2.35 2.40 2.452.20 2.50

-2

0

2

4

6

8

10

-4

12

freq, GHz

real(Z

in1)

Readout

m1

imag(Z

in1)

Readout

m2

m1freq=real(Zin1)=10.476

2.327GHz

m2freq=imag(Zin1)=-0.232

2.327GHz

43

L.P. Antenna S(1,1)

44

2.25 2.30 2.35 2.40 2.452.20 2.50

-3.5

-3.0

-2.5

-2.0

-1.5

-1.0

-0.5

-4.0

0.0

freq, GHz

dB

(S(1

,1))

L.P. Antenna gain and efficiency

Gain Based on input

power

Directivity Based on

radiated power

Efficiency = G/D

45

L.P. Antenna Polarization

• Gain is measured at max radiation 46

L.P. Antenna with Quarter-wave

Transformer Matching Network

m4freq=dB(S(1,1))=-45.317Min

2.326GHz

2.31 2.32 2.33 2.34 2.35 2.36 2.37 2.38 2.392.30 2.40

-40

-30

-20

-10

-50

0

freq, GHz

dB

(S(1

,1))

Readout

m4

m4freq=dB(S(1,1))=-45.317Min

2.326GHz

m3freq=S(1,1)=0.006 / 146.475impedance = Z0 * (0.990 + j0.007)

2.325GHz

freq (2.300GHz to 2.400GHz)

S(1

,1)

Readout

m3

m3freq=S(1,1)=0.006 / 146.475impedance = Z0 * (0.990 + j0.007)

2.325GHz

L.P. Antenna with Shorted Single-Stub

Matching Network

2.31 2.32 2.33 2.34 2.35 2.36 2.37 2.38 2.392.30 2.40

-40

-30

-20

-10

-50

0

freq, GHz

dB

(S(1

,1))

Readout

m4

m4freq=dB(S(1,1))=-42.985

2.326GHz

freq (2.300GHz to 2.400GHz)

S(1

,1)

Readout

m3

m3freq=S(1,1)=0.007 / -1.587impedance = Z0 * (1.014 - j3.984E-4)

2.326GHz

Circularly Polarized Design

49

• In progress

• Utilization of Momentum’s existing built in

optimization tool, or manual measurements of Lo

and S.

• Iwasaki Source gives f, εr, h has a small effect.

We can estimate position of the feed line

• S 12 – 18 % of total patch length

• W 34 – 46 % of offset range, measured from

the center to the edge of the patch width

Circularly Polarized Design

Circularly Polarized Design

Plan of Action

• Design a matching network for the linearly polarized antenna, fabricate, and

test.

• Finish design of the circularly polarized antenna, designing for minimum

axial ratio.

• Design the matching network for the circularly polarized antenna, fabricate,

and test

• Simulate the cascaded LNAs

• Fabricate and test the cascaded LNAs

– Outside services needed for fabrication

52

Original Timeline

53

Revised Timeline

54

1/23 –

1/26

1/27 –

2/2

2/3 –

2/9

2/10 –

2/16

2/17 –

2/23

2/24 –

3/1

3/2 –

3/8

3/9 –

3/15

3/16 –

3/22

3/23 –

3/29

3/30 –

4/5

4/6 –

4/12

4/13 –

4/19

4/20 –

4/26

4/27 –

5/3

Designspring break

Simulation/optimization

(linearly polarized

antenna) spring break

Simulation/optimization

(circularly polarized

antenna) spring break

Fabricate L.P. and C.P

Antenna and testing spring break

Simulation and

fabrication of cascaded

LNA board and testing

spring break

Incorporate both the

antenna and LNA and

test spring break

integrate with

commercial receiver

and test spring break

Presentation and Final

Project Report spring break

Questions

55