Microwave and Radio Frequency (RF) Engineering is seeing renewed interest by undergraduate students, not only in job opportunities that the wireless area affords, but also with students trying to understand what is 'under the hood' in the ubiquitous wireless devices they often (sometimes too often) use. A veritable alphabet soup of wireless applications (WiFi, WiMAX, RFID and ZigBee to name but a few) are not only in use now but wider bandwidth, faster wireless networks are projected for the future. In fact, the International Technology Roadmap for Semiconductors (ITRS) shows that RF and "wireless applications may replace computers as the key driver in manufacturing" over the next 10 years. In addition to the challenges in lower power applications, another key component of some wireless systems is the high power output amplifier that drives the antenna and is a major consumer of system (especially battery) power. Indeed, much work continues to be done in industry on high efficiency power amplifiers (PA) since in most portable wireless devices, the PA is often the most power-hungry of all the sub-systems, possibly even more than the digital processors. High efficiency is critical so that as much DC energy is converted to usable RF energy and not wasted in heating up the device. A number of schools have introduced RF design classes to fill this student interest. From the faculty member's perspective, the increased student interest in the wireless area as described above provides a wonderful opportunity to further enhance student learning and engagement in the area of system engineering, electronics and high frequency design and construction techniques. Some schools have used high frequency design classes from a theoretical perspective but with a lower frequency project component to illustrate the timeless concepts. Other schools are using the latest PC-soundcard based software defined radio (SDR) kits and ideas to illustrate receiver concepts as well as I/Q modulation schemes; PC software from external sources are used to process the I/Q signals from the hardware SDR and so there is a fear that some important concepts may be lost through the use of the 'black box' software. However, the hardware component is still invaluable for students to get an understanding of the material. This 'return to hardware basics' approach has been heavily utilized at Villanova University over the last few years with a number of courses and independent student projects that illustrate these receive and transmit principles. This paper will build on a series of past papers in outlining the senior level elective sequence as well as a series of high efficiency power amplifier projects undertaken as independent studies. All of these experiences are suitable for undergraduate students and with some modification, could be useful in graduate level courses.
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