This paper describes a two-stage 5-W broad-band amplifier covering the frequency range from 10 MHz to 2.4 GHz. An SiC MESFET is used as the power stage. A large-signal table-based model has been developed and verified for the SiC device by comparison with measurements. A novel broad-band choke structure was developed to obtain high dc isolation and low RF loss over the full bandwidth. No impedance transformer was used at all. Broad-band input and output matching networks and shunt feedback topology were introduced to fulfill the bandwidth requirements. Typical values of 22-dB power gain, 37-dBm output power, 28% power-added efficiency, and 47-dBm third-order intercept points have been achieved in a two-stage design using a GaAs MESFET as driver stage. All power and linearity results were obtained over the whole frequency band. The design procedure is given in detail and the results are being discussed and compared with simulations.

In this paper, a 1 MHz to 3.4 GHz, 5 W, highly linear power amplifier based on GaN HEMT is reported. Load-pull technique has been applied to introduce a compromising solution for the PA performance trade-off problem. Over the whole bandwidth a measured small signal gain of 14 ± 0.7 dB and an output return loss of better than -10 dB have been achieved. The input return loss was better than -10 dB up to 3 GHz. Power and linearity performances have been measured and compared to simulations resulting in a very good agreement. At a frequency spacing of 100 kHz, minimum values of output IP3 and output IP2 have been evaluated and found to be 48.5 dBm and 59.3 dBm. At 1 dB power compression point, minimum P out and G P were found to be 37.3 dBm and 13.3 dB, respectively within the whole frequency band.

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Abstract-Switch mode power amplifiers offer high efficiency approaching 100% for an ideal case. This paper discusses the operation mode of broadband switch mode class-E power amplifier designed previously by the authors for UHF applications (600-1000 MHz). A method to extract the waveforms at the die reference plane from the time domain analysis using 50 Ω environment systems is discussed. It has been observed that the designed class-E power amplifier operation was not maintained ideally over the entire band; however, it was operating close to the class-E operation.

A new design of dual band compact microstrip antenna is proposed for Ku-band applications.Dual band is achieved using three pairs of thin slits from the sides of a rectangular patch and feeding with a microstrip feed line.The result shows that a return loss of -32.9dB is achieved at the first resonant frequency of 12.72GHz, and -14.4dB is obtained at the second resonant frequency of 14.4GHz frequency with VSWR ≤ 2indicating improved matching conditions. The results ofsimulation are return loss, radiation pattern, VSWR, and band widtharepresented. The design is performed by using Ready-madeSoftware package Zeland-IE3D. The antenna is fabricated using thin film and photolithographic technique and measured using the Vector Network Analyzer. The final result shows that good agreement between the simulated and measured results.