Bandwidth and Efficiency Enhancement in Radio Frequency Power Amplifiers for Wireless Transmitters by Karun Rawat & Patrick Roblin & Shiban Kishen Koul

Author:Karun Rawat & Patrick Roblin & Shiban Kishen Koul
Language: eng
Format: epub
ISBN: 9783030388669
Publisher: Springer International Publishing

The family of solutions obtained for continuous class F PA design depends upon the parameter δ. Figure 4.13a shows the design space where multiple impedance solutions are possible for each frequency point. These solutions are based on the step of δ, range of δ, and frequency of operation. To overcome the problem of non-foster behavior of load at the package plane, design space must be investigated and values of parameter δ with frequency should be selected to provide realizable matching network as well as higher operating bandwidth. Since the projection of second harmonic loads to the package plane of the device is significantly expanded on the Smith chart compared to fundamental loads for a specified frequency range, its foster behavior for matching requirement becomes more critical. The optimum load can be decided by selection of range of δ with frequency and step size of δ with every change in frequency [4]. Step size of δ is defined as parameter k. Figure 4.13a shows the different cases with different values of k for the selection of δ with frequency for different k. In this design space analysis, the frequency points are considered to be 100 MHz apart. The selection of k has a direct impact on the bandwidth. One can see in Fig. 4.13a that the slope of δ can be taken positive or negative with increasing frequency. Also, step size of δ, that is, k, can be taken as a constant fixed value or variable. Based on the step size (k), the design space analysis is divided into two categories: (a) fixed value of k and (b) variable k.

Fig. 4.13(a)Variation of parameter δ with frequency for different k; (b) extrinsic impedances projected by embedding transfer network (ETN) for k = 0.5 and k = 0.025; (c) extrinsic impedances projected by ETN for k = 0.1 and for variable k [4]

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.