This document summarizes the design and development of a high power amplifier at 3.4 GHz for use in ranging transponders. It describes the design approach, including impedance matching networks to maximize power transfer. Simulation results show the power amplifier achieved over 27 dB of gain and met input and output return loss specifications of less than -10 dB after impedance matching. Biasing network design allowed the power amplifier to achieve 54% efficiency and output over 1 W of RF power. The document provides a literature review of similar power amplifier designs and aims to guide the design of a high power amplifier at 3.4 GHz suitable for use in ranging transponder applications.

1. DESIGN AND DEVELOPMENT OF HIGH POWER AMPLIFIER AT 3.4GHz
Neel Patel (140320705506)
Guided by: Asst. Prof. Nimesh M Prabhakar
L.J. Institute of Engineering and Technology
INTRODUCTION OF IRNSS
MATCHING NETWORK DESIGN
REFERENCES
HARMONIC BALANCE IN ADS
• Due to this output signal contains fundamental
frequency components and some undesired frequency
components, which are integral multiple of input signal
frequency. These additional frequency components are
called harmonics. Hence the output is said to be
distorted, this is called harmonic distortion.
1st Order Harmonic
f1=3GHz
f2=4GHz
3rd Order Harmonic
2f1-f2=2GHz
2f2-f1=5GHz
5th Order harmonic
3f1-2f2=100 MHz
3f2-2f1=6GHz
CONCLUTION
• In a communication satellite serving the earth, the
transponder transforms the received signals into
forms appropriate for the transmission from space
to earth. The transponder may be simply a repeater
that amplifies and frequency signals. In this paper,
the technologies of the major transponder elements
are presented and amplifying devices.
• The transmitter is required to amplify the wanted
signal without distortions and without other
impairments which would decrease the usefulness
of the signal. Two types of amplifiers (transmitters)
are in common use, electron beam devices
(commonly TWTAs) and solid state power
amplifiers (SSPAs). For the TWTAs, the electrical
power supply is often required to supply a number
of high voltages , which presents a series of
technology and design challenges. show in fig 1.
The Power Amplifier presented here does meet many of the
required specifications. The transistor is Stable for design
specifications.The choice of transistor in this power amplifier has
influenced the design specifications in an unexpected manner.
To make a power amplifier utilizing this device, a wide variety of
matching networks should be explored along with an
appropriate device modelling in ADS. Also Complete the
Impedance Matching , Biasing Network , Harmonics Balance.
RANGING
TRANSPONDER
MASTER
CONTROL
STATION
DIPLEXER RECEIVER BPF TRANSMITER
(PA)
ANTENNA
CDMA
6.7 GHz
3.4 GHz
Fig 1: Indian Regional Navigational Satellite System
DESIGN APPROACH
• The wireless communications in satellite transponder
increasing demands on systems designs.
• A critical element in Radio Frequency (RF) front ends
is the Power Amplifier (PA). Main specifications for PA
design include high linearity, better gain and
efficiency.
• The active device specified for this design was a
Rfmd SZA3044Z BJT. Table I shows the performance
specifications for the designed Power amplifier..
Parameter Symbol Specification
Frequency range fo 2.5-4.5 GHz
Gain S21 ≥15dB
Input return loss S11 ≤ -10dB
Output return loss S22 ≤ -10dB
Input/output
Impedance
Z0 50Ω
Output power P0 1W
Table 2 : Target Specification
• Impedance matching is required to maximize the power
transfer and minimize the reflections. Smith chart is
used for impedance matching. According to maximum
power transfer theorem, maximum power delivered to
the load when the impedance of load is equal to the
complex conjugate of the impedance of source (ZS=ZL*).
A. INPUT MATCHING NETWORK
• The first set of measurements we are taken for S11 with
the device mounted on the board and biased, but
without matching networks. These measurements were
de-embedded in ADS to obtain the input impedance at
the device terminal.
B. OUTPUT MATCHING NETWORK
• To design the output matching network, S22 of the
biased, unmatched system was measured and de-
embedded back to the device terminals. Simulations
were then performed to determine the impedance
presented to the drain that would maximize small signal
gain. The matching network was designed in the same
fashion as the input matching network.
Fig 2: Input & Output Matching Network Circuit In ADS
DC I/V CHARACTRISTICS
• We have to define the Output Power and Power
Efficiency of the Amplifier with the help of the DC IV
Characteristics.
• The Biasing condition Vce = 5V , Idc = 240 mA
• Result:
RF Output Power: 1.33W
DC Power Output: 2.47W
Efficiency=
𝑅𝐹𝑂𝑢𝑡𝑝𝑢𝑡 𝑃𝑜𝑤𝑒𝑟
𝐷𝐶 𝑜𝑢𝑡𝑝𝑢𝑡 𝑃𝑜𝑤𝑒𝑟
∗ 100%
=
1.33𝑊
2.47𝑊
*100%
=54%
Fig 5: Stability Factor
Fig 6 : Harmonic balance
Fig 9 : Harmonic Balance
Fig 7 : OrdersFig 8 : 1st & 3rd Order Output
RESULTS
Parameter Specification Measured
results
After
Impedance
Matching
Measure
d results
After
Biasing
Network
Gain S21 ≥15dB 26.412dB 27.064dB
Input return
loss
S11 ≤ -10dB -39.873dB -
15.440dB
Output
return loss
S22 ≤ -10dB -49.342dB -
15.725dB
Input/output
Impedance
Z0 50Ω 50Ω 50Ω
Table 3 : Measurement Results
BIASING NETWORK OF POWER AMPLIFIER
Fig 4 : Gain Of Power Amplifier
Fig 3 : After Biasing Network Of Power Amplifier
Fig 5: Stability Factor
• The power amplifier (PA), being one of the most
important blocks of the wireless communication
system, is no exception. Therefore, this document
presents a detailed study of the single-ended class-
A power amplifier, which is the configuration that
has good efficiency and easier integration, making it
one of the strongest candidates for a practical
implementation. The aim of this work is to provide
the study that guides the design of a high power
amplifier at 3.4 GHz for Ranging Transponder
applications.
ABSTRACT
LITERATURE SURVEY
Rf
No
Frequency Gain
(S21)
S11 S22 Efficiency
1 3.5GHz 33dB -10dB -10dB 30%
2 0.2 – 8GHz 13.2d
B
-9.1dB -12dB 39%
3 3.4GHz 14dB -10dB -10dB 25%
4 3.5GHz 16dB -30dB -31dB 45%
5 5.8GHz 9dB -19dB -19dB 50%
Table 1 : Literature Survey
1. Tomohiro Senju, Takashi Asano, Hiroshi Ishimura Microwave Solid-state Department “A
VERY SMALL 3.5 GHz 1 W MMIC POWER AMPLIFIER WITH DIE SIZE REDUCTION
TECHNOLOGIES” Komukai Operations Toshiba Corporation, Toshiba-cho, Saiwai-ku,
Kawasaki 2 12-858 1, Japan-2001 IEEE, pp. 070-073 ,ISBN:0-7803-7161-5/01.
2. Kevin W. Kobayashi, YaoChung Chen, Ioulia Smorchkova, Roger Tsai,Mike Wojtowicz,
and Aaron Oki “A 2 Watt, Sub-dB Noise Figure GaN MMIC LNA-PA Amplifier with Multi-
octave Bandwidth from 0.2-8 GHz” 2007 IEEE - SIRENZA MICRODEVICES, pp.619 -
622,ISBN:1-4244-0688-9/07.
3. Paul saad, christian fager, hossein mashad nemati, haiying cao, herbert zirath and
kristoffer andersson ” A highly efficient 3.5 GHz inverse class-F GaN HEMT power
amplifier” European Microwave Association International Journal of Microwave and
Wireless Technologies, 2010, 2(3-4), pp.317–332,DOI:10.1017.