Identification of memory terms in a power amplifier

Thesis Type: Postgraduate

Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Engineering, Department of Electrical and Electronics Engineering, Turkey

Approval Date: 2013


Supervisor: ŞİMŞEK DEMİR


Behavioral models are valuable tools which bring ability to simulate a device without knowing inside of the device. Behavioral modeling is functional in many areas. Power amplifier which is a crucial device for RF/Microwave systems is also an application area of behavioral modeling. Static Nonlinearity -AM/AM, AM/PM distortion- and Dynamic Nonlinearity –memory effect- are issues of power amplifier behavioral modeling. Memory effect is an undesired behavior seen in power amplifiers. Memory means output produced is not only determined by present input but also by previous inputs. Bandwidth of input signal, input power level, bias circuit components and semi-conductor characteristics are some sort of factors affecting memory. In this thesis, a behavioral model that exhibits memory effect is proposed. Model is constructed for a 1-2 GHz 10W output power (in saturation) class AB power amplifier. Approach applied is compared with previous modeling approaches and advantages of proposed model are presented. Additionally, relation between bias circuit components and memory is investigated.