The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
High frequency dc-dc switching converters are used as envelope amplifiers in RF transmitters. The dc-dc converter should operate at very high frequency to track an envelope in the MHz range to supply the power amplifier. One of the circuits suitable for this application is a hybrid topology composed of a switched converter and a linear regulator in series that work together to adjust the output voltage...
In order to optimize energy efficiency, some applications require adapting supply voltage according to the work load requirements. For example, in high performance digital systems and in RF systems, voltage scaling and modulation techniques have been adopted in order to achieve a more efficient processing of the energy. These techniques are based in rapidly adjusting the system supply voltage level...
A solution combining a multilevel converter in series with a linear regulator to obtain an envelope amplifier was presented recently in for EER. Two possible implementations of the multilevel cell are compared. In, a two-state topology for the multilevel cell is proposed for the envelope amplifier. The three-state cell topology, proposed in this paper, has two main advantages: less number of cells...
In radio systems linear power amplifiers (class A, B or AB) are usually used as a solution for the power amplifier stage. These amplifiers have high linearity, but suffer from low efficiency when the transmitted signal has low peak-to-average power ratio. The Kahn envelope elimination and restoration (EER) technique is used to enhance efficiency of RF transmitters, by combining highly efficient, nonlinear...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.