| 1. |
- Saad, Paul, 1983, et al.
(författare)
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Highly efficient GaN-HEMT power amplifiers at 3.5 GHz and 5.5 GHz
- 2011
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Ingår i: 2011 IEEE 12th Annual Wireless and Microwave Technology Conference, WAMICON 2011. - 9781612840819
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Konferensbidrag (refereegranskat)abstract
- This paper reports the design, implementation, and experimental results of two high efficiency GaN-HEMT power amplifiers (PAs) at 3.5 GHz and 5.5 GHz. A bare-die approach is used to eliminate package parasitics in conjunction with an in-house transistor model that enables investigation of the transistor intrinsic waveforms. With this as a basis, harmonic source-pull/load-pull simulations have been used to design and implement two state-of-the-art highly efficient harmonically tuned PAs. For the 3.5-GHz PA, large-signal measurement results show a PAE of 80%, a power gain of 15.5 dB, and an output power of 7 W, while for the 5.5-GHz PA, 5.6 W output power, 12.5 dB power gain, and 70% PAE are achieved.
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| 2. |
- Wang, Y., et al.
(författare)
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Feasibility study of pico cellular-relaying system in urban outdoor environment
- 2011
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Ingår i: 2011 IEEE 12th Annual Wireless and Microwave Technology Conference, WAMICON. - 9781612840819
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Konferensbidrag (refereegranskat)abstract
- Heterogeneous networks, in particular cellular-relaying networks, have the potential to provide high data-rate services at low infrastructure costs. Macro and micro base stations have traditionally been used to provide coverage and capacity, respectively. In this paper, we analyze a new approach in which coverage is provided by means of inband relays. We show that compared with a traditional network based on macro base stations, a good outdoor coverage for a target data rate could be provided in a more cost efficient way by deploying a network based on pico base stations and relays. However, this is valid only for low data-rate because part of the spectrum is allocated to the backhaul and therefore the capacity of cellular-relaying networks is typically limited. Moreover, this break-even point depends on how the networks are deployed.
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| 3. |
- ÖZEN, MUSTAFA, 1984, et al.
(författare)
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High efficiency RF pulse width modulation with tunable load network class-E PA
- 2011
-
Ingår i: 2011 IEEE 12th Annual Wireless and Microwave Technology Conference, WAMICON 2011. - 9781612840819
-
Konferensbidrag (refereegranskat)abstract
- In this paper, a 10 W peak power 2 GHz highly efficient RF pulse width modulation (RF-PWM) based transmitter is presented. RF-PWM signals are generated with a dedicated 65 nm CMOS modulator and subsequently amplified with a GaN Class-E power amplifier (PA). The modulator use extended drain MOS (EDMOS) high voltage transistors to provide the required voltage swing to drive the GaN used as a switch. The imaginary load impedance of the Class-E is electronically tunable and is implemented with in-house high breakdown voltage SiC varactors. The tunable imaginary load impedance enables optimization of the Class-E versus the duty cycle (pulse width). The peak efficiency is therefore preserved over a wide range of output power levels. The measured drain efficiency of the Class-E output stage is above 70% over a 6.5 dB output power dynamic range. The overall transmitter efficiency is above 60% for the same dynamic range.
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