1,721,183 research outputs found
A GaN-on-Si MMIC Power Amplifier with 10W Output Power and 35% Efficiency for Ka-Band Satellite Downlink
No full textThe design and experimental characterization of a Monolithic Microwave Integrated Circuits (MMICs) Power Amplifiers (PAs) specifically conceived for next generation Ka-band Very High Throughput Satellites (vHTS) are discussed. The chip has been implemented on a commercially available 100 nm gate length Gallium Nitride on Silicon (GaN-Si) process. The design was carried out accounting for the peculiarities of the application, therefore the selection of the devices' bias points and the matching network topologies was driven, and then accomplished, by carefully considering the thermal constraints of the technology, in order to keep the junction temperature of all devices below 160°C. The MMIC, based on a three stage architecture, has been fully characterized from 17.3 GHz to 20.2 GHz. In such a frequency range, it delivers an output power larger than 40 dBm with a power added efficiency peak higher than 40% and 22 dB of gain
A High Efficiency and Low Distortion 6 W GaN MMIC Doherty Amplifier for 7 GHz Radio Links
No full textEmpowering the Bandwidth of Continuous-Mode Symmetrical Doherty Amplifiers by Leveraging on Fuzzy Logic Techniques
Full text linkA GaN-SiC MMIC Doherty Power Amplifier For K-band Wireless Communications
No full textThis work presents the design and measurement results of a Monolithic Microwave Integrated Circuit (MMIC) Doherty Power Amplifier (DPA) conceived for K-band wireless applications. The amplifier is based on a two-stage architecture in which a single device drives both Carrier and Peaking final stage. The selected technology is the Gallium Nitride on Silicon Carbide (GaN-SiC) HEMT with 0.15 mu mathrm{m} gate length, supplied by WIN Semiconductors foundry. The center frequency is set to 19.65 GHz, whereas the chip area results to be 3.7 times 3 mathrm{~mm}{2}. From the preliminary experimental characterization, a good agreement between measurements and simulations has been achieved. Small-signal gain in excesses of 16 dB has been measured from 18.65 GHz to 20.65 GHz with both input and output return losses better than 10 dB. Expected nonlinear performance in terms of output power, power added efficiency (PAE) and gain at saturation and back-off level are respectively: P {text{out}, text{sat}}=36 mathrm{dBm}, P A E {text {sat }}=40 %, G {text {sat }}=13 mathrm{~dB} and P {text {out,back-off }}=30 mathrm{dBm}, PAE {text {back-off }}=25 %, mathrm{G} {text {back-off }}=14.5 mathrm{~dB}
A Design Approach to Maximize the Efficiency vs. Linearity Trade-Off in Fixed and Modulated Load GaN Power Amplifiers
No full textThis paper proposes a design method to minimize the phase distortion (AM/PM) in Gallium Nitride (GaN) Power Amplifiers (PAs), without significantly worsening other key features such as efficiency, amplitude distortion and gain. The design strategy consists in the adoption of a smart two-stage architecture, in which the driver stage is devised to act as a sort of “analogue AM/PM predistorter” for the final one. Accounting for the actual trend in PA solutions, the proposed approach has been fine-tuned to implement a two way class AB PA and a Doherty Power Amplifier (DPA) for backhaul radio links. Both circuits, realized on the same 0.25μm GaN technology and in monolithic form, have fully been characterized with continuous wave (CW) and modulated signals. At 7 GHz the DPA shows 38dBm of saturated output power and less than 3° of phase distortion, with a power added efficiency (PAE) higher than 41% in 6 dB of power back off. The class AB PA achieves almost the same level of saturated output power and maximum PAE, with an inevitable lower efficiency in back off operation, whereas the registered AM/PM is lower than 1.5°. Moreover, when tested with modulated signals, at 32dBm of average output power and without any digital predistortion, the DPA shows a spectral regrowth of around 36 dBc and a PAE of 40%, whereas the class AB PA achieves 40 dBc and 30%, respectively
Enhancing power efficiency of doherty power amplifiers using windowing based crest factor reduction technique
No full textThis paper investigates the performance of a Windowing Based Crest Factor Reduction (CFRWB) technique, to enhance the power efficiency of Radio Frequency (RF) power amplifiers. In particular, CFRWB is implemented on a Doherty Power Amplifier (DPA) in conjunction with Generalized Memory Polynomial (GMPDPD), and Volterra series based Digital Predistortion (VDPD) techniques. Key features like spectral regrowth, Peak to Average Power Ratio (PAPR) reduction, efficiency improvement and Error Vector Magnitude (EVM) have been used to measure the efficacy of the proposed method. Both simulation and experimental results show that the proposed combination of CFRWB technique with GMPDPD and VDPD is able to reduce the PAPR of the complex input signals by nearly 60%, with minimal degrading of the EVM and spectral regrowth. Moreover, such signal with reduced PAPR can be used to overdrive the DPA, allowing for a relevant average efficiency enhancement (i.e., up to 25%), while fulfilling the requirements of modern communication standards such as Wideband Code Division Multiple Access (WCDMA) and long-term evolution (LTE)
GaN MMIC High Power Amplifiers for K-Band Satellite Payload
No full textThis contribution presents the activities carried out towards the realization of a high-power solid state power amplifier, based on Gallium Nitride (GaN) technology, targeting more than 125W of output power in the frequency range 17.320.2 GHz, conceived for the next generation K-band Very High Throughput Satellites (vHTS). For this purpose, specific Monolithic Microwave Integrated Circuits (MMICs) Power Amplifiers (PAs) were developed on a commercially available 100 nm gate length GaN on Silicon (GaN-Si) process (OMMIC process D01GH). The design was carried out considering space reliability constraints on electrical parameters and accounting for the spacecraft temperature limits, which are extremely challenging for this technology, to keep the junction temperature of all devices below 160{circ}mathrm{C} in the worst-case condition (i.e., maximum environmental temperature of 85{circ}mathrm{C}). The final MMIC, based on a three-stage architecture, demonstrates on wafer and in pulsed condition to achieve a minimum output power and power added efficiency (PAE) of 10W (40dBm) and 35% (with a peak of 45%) in the full Ka-band satellite downlink, i.e., from 17.3 GHz to 20.2 GHz. The packaged version demonstrates in continuous wave (CW) conditions an output power larger than 39.5dBm with a PAE better than 30%. Moreover, long-term (24h) CW test at saturated output power has shown almost negligible performance degradation, thus providing confidence in the robustness of the selected GaN-Si technology
A high efficiency 10W MMIC PA for K-b and satellite communications
Full text linkThis paper discusses the design steps and experimental characterization of a monolithic microwave integrated circuit (MMIC) power amplifier developed for the next generation of K-band 17.3–20.2 GHz very high throughput satellites. The technology used is a commercially available 100-nm gate length gallium nitride on silicon process. The chip was developed taking into account the demanding constraints of the spacecraft and, in particular, carefully considering the thermal constraints of such technology, in order to keep the junction temperature in all devices below 160°C in the worst-case condition (i.e., maximum environmental temperature of 85°C). The realized MMIC, based on a three-stage architecture, was first characterized on-wafer in pulsed regime and, subsequently, mounted in a test-jig and characterized under continuous wave operating conditions. In 17.3–20.2 GHz operating bandwidth, the built amplifier provides an output power >40 dBm with a power added efficiency close to 30% (peak >40%) and 22 dB of power gain
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