Microwave-to-dc rectification is valuable in many applications, including RF energy recovery, dc-dc conversion, and wireless power transfer. In such it desired for the microwave rectifier system to provide a constant input impedance. Consequently, variation impedance over varying incident levels can hurt performance. To address this challenge, we introduce multiway transmission line resistance compression networks (TLRCNs) maintaining near-constant RF-to-dc systems. A development of TLRCNs...

This paper presents an octave-bandwidth load modulated balanced amplifier (LMBA) that operates directly on a single RF input. The architecture is based the recently proposed LMBA technique, in which control signal applied at output isolation port of used to modulate apparent impedance two devices comprising amplifier. In our approach, injected both as active match and dynamically main provide efficiency enhancement back-off, thus extending dynamic range compared original formulation. this...

We present a 2.4-GHz asymmetric multilevel outphasing (AMO) power amplifier (PA) with class-E branch amplifiers and discrete supply modulators integrated in 65-nm CMOS process. AMO PAs achieve improved modulation bandwidth efficiency over envelope tracking (ET) by replacing the continuous modulator implemented fast digital switching network. Outphasing is used to provide required fine output control. The PA delivers 27.7-dBm peak 45% system at 2.4 GHz. For 20-MHz WLAN OFDM signal 7.5-dB...

This paper presents an analysis and design technique for RF-input load modulated balanced amplifier (LMBA) with Doherty-like efficiency enhancement characteristics. The LMBA is a recently introduced power (PA) architecture in which control signal injected into the isolation port of output coupler amplifier. modulates apparent impedance two main devices. In presented this paper, generated from single-modulated RF input using class-C amplifier, producing overall response. A complete...

This work presents a development of multi-way transmission-line resistance compression networks (TLRCNs) and their application to rf-to-dc conversion. We derive analytical expressions for the behavior TLRCNs, describe two design methodologies applicable both single- multi-stage implementations. A 2.45-GHz 4-way TLRCN network is implemented applied create resistance-compressed rectifier system that has narrow-range resistive input characteristics over 10-dB power range. It demonstrated...

Performing RF amplification in a way that is simultaneously linear and efficient has long been challenge power amplifier (PA) design. In short, single-transistor PAs can either be operated (but inefficient) current-source mode of operation or as nonlinear) switches, but these two modes are mutually exclusive. The outphasing concept explored to address this tradeoff by using nonlinear elements an architecture providing output control.

This article presents 16and 81-element broadband rectenna arrays screen printed on a cotton tee-shirt for harvesting 4-130-μW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> power densities between 2 and 5 GHz. A packaged SMS7630-079LF Schottky diode is connected with silver paint soldered to each element of the array. The impedance over frequency as function dc load input analyzed using source-pull harmonic-balance simulations....

Conventional outphasing power amplifier systems require both a radio frequency (RF) carrier input and separate baseband to synthesize modulated RF output. This work presents an RF-input/RF-output that directly amplifies input, eliminating the need for multiple costly IQ modulators signal component separation as in previous systems. An decomposition network synthesizes phase- amplitude-modulated signals used drive branch amplifiers (PAs). With this approach, including zero-crossings can be...

A lossless power-combining network comprising cascaded transmission-line segments in a tree structure is introduced for multi-way outphasing architecture. This architecture addresses the suboptimal loading conditions Chireix transmitters while offering compact and microwave-friendly implementation compared to previous techniques. In proposed system, four saturated power amplifiers (PAs) interact through an all-TL produce nearly ideal resistive load modulation of branch PAs over 10:1 range...

A new design methodology providing optimal mixed-mode operation for dual-input class-F outphasing Chireix amplifiers is presented. The starts with single-transistor simulations at the intrinsic I-V reference planes to directly select peak and backoff resistive loads R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">min</sub> xmlns:xlink="http://www.w3.org/1999/xlink">max</sub> input RF gate drives yielding best combination of efficiencies output...

A lossless multi-way outphasing and power combining system for microwave amplification is presented. The architecture addresses one of the primary drawbacks Chireix outphasing; namely, sub-optimal loading conditions branch amplifiers. In proposed system, four saturated amplifiers interact through a network to produce nearly resistive load modulation over 10:1 range output powers. This work focuses on two microstrip-based combiner implementations: hybrid microstrip/discrete implementation...

This paper demonstrates a high-efficiency dualband RF power amplifier (PA) for sub-6 GHz 5G carrier aggregation. The dual-band PA is tested with modulated signals generated by new algorithm designed to provide realistic waveforms aggregation scenarios, allowing flexible complex (IQ) sequences arbitrary peak-to-average ratio (PAPR), bandwidth, and band distribution. A single-stage packaged 6-W transistor diplexer-like output matching network that separates the two bands into outputs. It...

This work presents a load modulated balanced amplifier (LMBA) that directly amplifies RF input. The architecture is based on the recently proposed LMBA technique, in which control signal applied at output hybrid of used to modulate apparent impedance two main devices. Here, we eliminate need for an externally-generated signal. Instead, and simply synthesized from input, allowing function as RF-input / RF-output power amplifier. technique demonstrated 700-850 MHz with peak efficiency 63.2% CW...

This paper presents a broadband efficient power amplifier (PA) targeting sub-6-GHz 5G base station applications. Due to the demanding requirements in both peak-to-average ratio (PAPR) and bandwidth systems, we employ combination of load supply modulation for efficiency enhancement. Active matching, implemented using an RF-input load-modulated balanced (LMBA) architecture, enables octave-bandwidth operation. Supply modulation, which is carrier frequency agnostic, then used further extend...

This paper describes an electromaanetic circuit model of three ohase transformers capable includina ferromacanetic non-linear effects includinga hvsteresis, suitable for anv number windinas with a variety interphase connections and applicable to any magnetic confiauration. In particular, the common types circuits are considered i. e. (1) bank sinqle phase cores (2) limbb core (3) five limmb core. The is applied tne solution inrush currents in situations results shown compare favourably...

Modulation of load impedance is an effective way to maintain efficient power amplifier (PA) operation over high dynamic range modulated signals. For efficiency, a modulation approach can be applied inherently classes PAs such as those with harmonic tuning: Class J, F, and Inverse F. This paper presents analysis harmonically tuned (HT) amplifiers operating under conditions, deriving the optimal loading trajectories for these multiple operation. Because are complex, it then shown-through...

We describe a new outphasing transmitter architecture in which the supply voltage for each PA can switch among multiple levels. It is based on asymmetric multilevel (AMO) modulation technique increases overall efficiency over much wider output power range than standard LINC system while maintaining high linearity. For demonstration, simulated 65 nm CMOS process with HSUPA and WLAN signals. The simulation results show an improvement from 17.7% to 40.7% at 25.3 dBm 11.3% 35.5% 802.11g 22.8...

This paper presents a dynamic characterization of multilevel (ML) Chireix outphasing (ML-CO) power amplifier (PA) with modulated signals. The ML-CO technique combines the advantages envelope tracking and architectures by limiting supply modulation to discrete levels an efficient power-DAC modulator using for fine amplitude control. We describe experimental test bench that supplies required phase- time-aligned signals simultaneously. Pulsed is used design ML memoryless polynomial DPD....

This letter presents a 2.14 GHz, four-way power combining and outphasing system for high-power amplifiers such as those in radio basestations (RBS). The combiner is ideally lossless, enables control through load modulation of the (PAs). A discrete-component designed characterized, combined with inverse Class-F PAs using GaN HEMT devices to develop complete PA system. We demonstrate effectiveness over range angles. first-ever microwave implementation has peak CW drain efficiency 68.9%,...

A 1.95-GHz asymmetric multilevel outphasing (AMO) transmitter with class-E GaN power amplifiers (PAs) and discrete supply modulators is presented. AMO transmitters achieve improved efficiency over envelope tracking (ET) by replacing the continuous modulator a implemented fast digital switching network. Outphasing modulation used to provide required fine output control. 4-level that allows for efficient up 28-V voltages using low-voltage gate drivers time-alignment logic. With two PAs 62.5%...

This paper presents a radio-frequency power amplifier (RF PA) with load impedance sensing circuitry incorporated into its output matching network (OMN), but without insertion of series elements the RF transmission path, limiting impact on performance. The approach is based multi-port reflectometry, such as can be used in sampled-line sensors, generalized to an arbitrary linear and applied existing OMN PA. With addition samplers OMN, offline computation performed determine complex reflection...

We present a high-efficiency transmitter architecture based on asymmetric multilevel outphasing (AMO), but with new method of generating discrete amplitude levels from the constituent amplifiers. AMO and LINC (ML-LINC) transmitters improve their efficiency over by switching supplies power amplifiers (PAs) among set voltages. This allows them to minimize occurrence large angles. However, it is also possible generate amplitudes varying duty cycle waveform that drives PAs. The chief advantage...

This work presents multi-level supply modulation of a load modulated balanced amplifier (LMBA). The RF-input LMBA employs dynamic active matching for efficient operation over an octave bandwidth. Supply is natural candidate to further enhance the back-off efficiency this broadband due its independence on RF carrier frequency. In ET-LMBA prototype demonstrated here, hybrid converter (power DAC) produces levels from 10 30 V modulate drain amplifier. Digital predistortion used linearize...