Pojačavači snage u klasi A sa istovremenim konjugovanim prilagođenjem i prilagođenjem po snazi pri velikim signalima na izlaznom pristupu
Power amplifiers in class a with simultaneous conjugate and large signal power matching at the output port
Author
Milićević, MilenkoMentor
Grujić, Dušan N.
Committee members
Saranovac, Lazar
Đurić, Radivoje
Radić, Jelena
Ilić, Milan

Metadata
Show full item recordAbstract
Disertacija se bavi razvojem metodologije projektovanja i unapre enjem topologija
pojacavaca snage u klasi A sa istovremenim konjugovanim prilago enjem i
prilago enjem po snazi pri velikim signalima na izlaznom pristupu.
Jedan od osnovnih zahteva za svaki pojacavac snage jeste efikasnost. U slucaju
pojacavaca snage u klasi A, tranzistor treba prilagoditi po snazi pri velikim signalima
na izlaznom pristupu da bi se opterecenju predala maksimalna moguca snaga.
Osim prilago enja po snazi, pojacavaci male i srednje snage cesto moraju biti
i konjugovano-kompleksno prilago eni na izlaznom pristupu. Ovaj zahtev je bitan
pošto je uobicajeno da je sledeci stepen projektovan tako da optimalno radi
kada je konjugovano-kompleksno prilago en na ulaznom pristupu. Pojacavaci male
i srednje snage su obicno implementirani u standardnoj complementary metal-oxide
semiconductor (CMOS) tehnologiji, dok naredni stepen može biti filtar za potiskivanje
neželjenih harmonika ili pojacavac snage napravljen u nek...oj od III-V generacija
poluprovodnicke tehnologije sa znatno vecom izlaznom snagom.
Standardni pojacavac sa zajednickim sorsom može biti prilago en po snazi pri
velikim signalima ili konjugovano prilago en na izlaznom pristupu, ali se oba prilago
enja ne mogu, u opštem slucaju, ostvariti istovremeno. Da bi se prevazišlo
pomenuto ogranicenje, predložena je topologija pojacavaca sa drejn-gejt povratnom
spregom kao i kompletna metodologija projektovanja. U svrhu verifikacije razvijene
teorije, projektovan je širokopojasni pojacavac snage u 130 nm RFCMOS tehnologiji.
Postignuta je maksimalna izlazna snaga od 7 dBm i efikasnost od 20%, u opsegu
ucestanosti od 6 do 9 GHz. Koeficijent refleksije na ulaznom i izlaznom pristupu je
manji od -8,5 dB i -9,5 dB, redom.
The dissertation deals with the development of design methodology and the
enhancement of topology of power amplifiers in class A with simultaneous conjugate
and power matching for large signals at the output port.
One of the major demands for any power amplifier is power efficiency. In the
case of a power amplifier in Class A, the transistor needs to be power matched for
large signals at the output port in order to deliver maximum power to the load.
This criterion is particularly important in the case of an amplifier with an output
power of the order of 30 dBm or more.
In addition to power matching, small and medium power amplifiers often have
to be conjugately matched at the output port as well. This requirement is important
because it is quite common that the next stage is designed so that it works
optimally when it is conjugately matched at the input port. Small and medium
power amplifiers are usually implemented in standard complementary metal-oxide
semiconductor CMOS technology, w...hile the next stage can be a filter for suppressing
unwanted harmonics or a power amplifier made in one of the III-V generations of
semiconductor technology with significantly higher output power.
A standard common-source amplifier can be designed to be either large signal
power matched or conjugately matched at the output port, but not both of them
at the same time. In order to overcome the mentioned limit, we propose a simple
topology based on a drain-gate feedback amplifier, together with a complete design
methodology. For the purpose of verifying the developed theory, a broadband power
amplifier is designed in 130 nm RFCMOS technology. The amplifier achieves 7 dBm
peak output power and maximum power efficiency of about 20% in the frequency
range from 6 to 9 GHz. Input and output return loss are better than 8.5 and 9.5
dB, respectively.