High-efficiency push-pull power amplifier integrated with quasi-Yagi antenna

Abstract

This paper presents a -band push-pull power amplifier integrated with a modified uniplanar quasi-Yagi antenna. In this circuit, corrugation is added to the truncated ground plane of the antenna so that it can be used for both out-of-phase power combining and second harmonic tuning. By using the active integrated antenna concept, this novel circuit eliminates the usage of an ordinary 180 hybrid at the power-amplifier output stage, therefore eliminating the losses associated with the hybrid, resulting in a compact and high-efficiency power-amplifier design with intrinsic second harmonic suppression. At an operating frequency of 4.15 GHz, a maximum measured power-added efficiency (PAE) of 60.9% at an output power of 28.2 dBm has been achieved. The measured PAE is above 50% over a 260-MHz bandwidth. Additionally, the second harmonic radiation is found to be 30 dB below the fundamental in both -and -planes. When the circuit is subjected to a two-tone test, the measured third-order intercept point is 37 dBm, about 10 dB above the 1 dB point.Index Terms-Active integrated antenna, FET amplifier, harmonic tuning, power-added efficiency, push-pull power amplifier.

A proposed defected microstrip structure (DMS) behavior for reducing rectangular patch antenna size

“…However, the DGS behavior has not been used in patch-antenna size reduction, since most reported applications of DGS in patch antennas are related to harmonic suppression [6,7,10] and bandwidth improvement [11]. To reduce the antenna size, a shape modification short-circuited /4 antenna has been reported [8], which is inherently of smaller size than the conventional one, but radiation efficiency, gain, and radiation pattern are modified.…”

Broadband high-efficiency linearly and circularly polarized active integrated antennas

“…Drain efficiency of Manuscript 100% can be achieved when the transistor is driven heavily into saturation. High-efficiency active antenna designs have been reported in [3] with push-pull PAs, [4] class-E PAs, and [5] class-F PAs. Circularly polarized (CP) antennas are useful for satellite communications and GPS system, as circular polarization will keep the signal constant regardless of anomalies or rotation.…”

“…In order to obtain the optimized solution from the given circuit configuration, it is necessary to minimize the difference between the optimum impedance and the actual impedance over a frequency bandwidth from to , i.e., it is necessary to minimize the error function (2) over the frequency range from to with respect to the circuit design parameters . The circuit input impedance is given by (3) where is the quality factor of the parallel tuned circuit.…”

5GHz Si-CMOS differential power amplifier module with directly connected dipole antenna

“…A Power amplifier (PA) directly connected to a radio frequency (RF) antenna, so called active integrated antenna concept, has been popularly investigated for a compact RF module [1,2,3,4,5]. The concept has the advantage of placing the PA at the antenna substrate with minimal matching and interconnects.…”

“…In previous works, discrete transistors of compound semiconductors were used for differential PA module with an antenna [2,3]. Peripheral chip components were necessary for circuits using discrete transistors, so that it was not suitable for compact configuration.…”