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MOSFETs for RF Applications
Published in Frank Schwierz, Hei Wong, Juin J Liou, Nanometer CMOS, 2010
Frank Schwierz, Hei Wong, Juin J Liou
The output power level required to be delivered from an RF power amplifier depends strongly on the particular application, and it can vary over several orders of magnitude from 1 mW to several hundreds watts. For example, the output power range of the power amplifiers for Zigbee and Bluetooth applications operating around 2.4 GHz is between 1 and 100 mW. For Bluetooth transmitters with a transmitting range of 10 m, the needed output power is 1 mW (0 dBm), and the powers are increased to 2.5 mW (4 dBm) and 100 mW (20 dBm) for 20-m and 100-m transmitting ranges, respectively. Concerning cellular phone systems, the output power of the power amplifier in a handset is around 1W, while the power amplifier module in a base station needs to deliver 300–500 W. Naturally, the output power capability of an RF power amplifier is directly proportional to the power performance of the RF transistors used in constructing such an amplifier.
Motivation Behind High Electron Mobility Transistors
Published in D. Nirmal, J. Ajayan, Handbook for III-V High Electron Mobility Transistor Technologies, 2019
In space applications, such as satellite communication systems, the RF power amplifier is one of the key components. In the amplifiers, a high PAE is important in order to reduce the launch cost of a satellite. C-band amplifiers, in the frequency range of 3.7–4.2 GHz, are often used for satellite downlinks. In spite of the tremendous merits of SSPAs, GaAs based amplifiers cannot typically offer an acceptable PAE for many satellite applications and the GaN HEMT SSPA, with its higher PAE, is expected to be the best candidate for replacing TWTAs. Many organizations have recently developed GaN HPAs at C-band. However, there are very few reports for HPAs with more than 60% PAE.
Semiconductors in Mobile Telecommunications
Published in Saad Z. Asif, 5G Mobile Communications Concepts and Technologies, 2018
An RF power amplifier is a type of electronic amplifier that is used to convert a low power radio frequency signal into a signal of significant power able to be transmitted over greater distances. Power amplifiers are normally designed for specific applications or standards (e.g. point-to-point microwave radios, LTE, etc.) [22].
Design of a Class-F Power Amplifier with GaN Device Model and Reflection Data
Published in IETE Journal of Research, 2023
Merve Alemdag, Firat Kacar, Sedat Kilinc
Growing popularity of the wireless communication systems demands low cost, high efficiency, and compact amplification solutions. An RF power amplifier which is the final amplification stage of an any RF transmitter chain is also known to be the most critical and power consuming building block. There has been a significant effort to increase the efficiency of power amplifiers [1–3]. Therefore, there is a considerable requirement to improve the performance and the PAE of power amplifiers. There are also requirements to improve compact techniques and approaches to design such circuits. Among developments and solutions for different classes of amplifiers, Class F PA have drawn the most attention from designers because of its capability of outputting high power and providing excellent power-added efficiency. A class F power amplifier can theoretically achieve 100% drain efficiency by shaping the intrinsic drain voltage and current waveforms [4]. There are also other several types of waveform engineered PA designs to improve efficiency investigated and explained in detail [5–9].
A Holistic Experimental Static Bias Point Identification Method for Low Power Wireless RF Amplifier
Published in IETE Journal of Research, 2022
Saroj K. Patro, Rabindra K. Mishra, Ajit K. Panda
It is shown that there are sweet spots for the device gate biasing of the RF power amplifier which needs to be investigated with a detail test methodology. For maintaining best efficiency and acceptable linearity, it is very much required to obtain these non-obvious bias points through detail test strategy which ensures the PA circuit to be simpler and cost-effective. For the low power BS applications, the optimum static mode of device biasing is an effective method for the stand-alone as well as for a linearized configuration. The proposed holistic experimental treatment of the power amplifier bias point investigation process is addressing some of the novel outcomes of the of device performance aspects which are not yet reported before to the best of our knowledge. Our method is mainly useful for the low power BS applications having average RF conducted power levels of much lower than 1 watt (i.e. in the order of 100 milliwatts to 1 watt range). This method could prove to be a very useful tool for defining and implementing a well-structured design verification strategy for high-efficiency amplifiers.
Interaction of circumferential SH0 guided wave with circumferential cracks in pipelines
Published in Nondestructive Testing and Evaluation, 2021
Wenze Shi, Weiwei Chen, Chao Lu, Yao Chen
The experimental setup and instruments are depicted in Figure 16. A generating EMAT and a receiving EMAT were used to excite and receive SH0 guided waves in the circumferential direction of the pipe. Figure 16(a) shows the SH guided-wave EMAT experimental system. A signal generator (Agilent 33120A) was used to provide a weak sinusoidal pulse signal. The weak pulse signal was amplified by an RF power amplifier (RETIC GA-2500A). With an impedance matching network in the EMAT excitation circuit, the maximum power could be transferred to the generating EMAT. The receiving EMAT could receive SH guided waves travelling in the pipe. With the help of an impedance matching network, a preamplifier (5077PR), and a band filter in the EMAT detection circuit, the amplitude and the signal-to-noise ratio (SNR) of the received ultrasonic wave signal could be significantly improved. The analogue A-scan signal was converted to a digital signal by the data acquisition card (NET8544), and it could be displayed in the software interface.