A majority of people now have a digital mobile device whether it be a cell phone, laptop, or blackberry. Now that we have the mobility we want it to be more versatile and dependable; RF power amplifiers accomplish just that. These amplifiers take a small input and make it stronger and larger creating a wider area of use with a more robust signal. Switching mode RF amplifiers have been theoretically possible for decades, but were largely impractical because they distort analog signals until they are unrecognizable. However, distortion is not an issue with digital signals-like those used by WLANs and digital cell phones-and switching mode RF amplifiers have become a hot area of RF/wireless design. This book explores both the theory behind switching mode RF amplifiers and design techniques for them. *Provides essential design and implementation techniques for use in cma2000, WiMAX, and other digital mobile standards *Both authors have written several articles on the topic and are well known in the industry *Includes specific design equations to greatly simplify the design of switchmode amplifiersCb C C0 L 0 Zin=R+jIL R L CL V cc Z0, Ir/4 FIGURE 9.18 transmission line produces a short circuit at its input for even ... a series quarterwave transmission line can serve as an impedance transformer at the fundamental frequency. In this case, there is no need for an additional output impedance matching circuit required for a Class-FE power amplifier with a parallel quarterwave transmission line.
|Title||:||Switchmode RF and Microwave Power Amplifiers|
|Author||:||Andrei Grebennikov, Nathan O. Sokal, Marc J. Franco|
|Publisher||:||Academic Press - 2012|