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Chopper stabilization is the most widely used circuit technique to reduce the influence of the flicker noise in an amplifier. Recently, observation of /ƒ2 input-referred noise in the chopper amplifier with a high-impedance input source was reported. However, the mechanism of this /ƒ2 phenomenon has not been completely analyzed. This paper provides the complete analysis of the noise influence generated...
This paper presents the current offer and the on-going development of United Monolithic Semiconductors (UMS) regarding RF chipsets for AESA Radar. UMS has developed a wide range of RF chipset covering AESA Radar applications from L to Q-band. These products have been developed on in-house UMS GaAs PHEMT and HBT technologies offering state of the art electrical performance and high reliability level...
This paper provides an overview of translational or com-mutated circuits and their role in RF receivers. Insights are offered into the frequency translation of impedances, their modeling, and their application in input matching, blocker rejection, and channel selection. A new front end is also described that rejects blockers at the third harmonic of the local oscillator frequency.
A 2.4GHz novel RF Mixer with folded structure designed in 180nm RF-Mixed signal technology has been investigated. It is implemented by using double balanced transconductance switch (GmSw) configuration. The proposed mixer converts incoming signal to small signal RF current followed by PMOS current mirror structure. The circuit is designed and optimized such that it can operate at less than 1.8V of...
Isolation of supply noise between disparate circuit blocks is crucial. When powered by the same voltage supply, the switching noise created at the supply node of the digital devices can couple into the power path of the RF circuitry and cause significant performance degradation. Electromagnetic bandgap (EBG) structures, ferrite beads, and split planes are all commonly used to mitigate this problem,...
Envelope tracking (ET) RF power amplifiers are emerging from decades of research as practical approaches for highly efficient, highly linear, broadband power amplification. Many aspects of ET power amplifiers are ideally suited for modern wireless communications - they work well across a wide frequency range, they are amenable to high levels of integration at the mobile terminal level, and they will...
A low-power, high linearity and wideband passive mixer for SDR is presented The passive mixer employs the improved current-reuse Gm stage, combines source degeneration with MGTR to extend the linearity region while enhance the IIP3 performance Measured results show the design achieves a good linearity even though the power of input RF signal is up to −14dBm (Vpp is about 160mV, consider the balun's...
A harmonic noise frequency filtering (HNFF) LC voltage-controlled oscillator (VCO) is fabricated using asymmetric inductance tank (AIT) in InGaP/GaAs heterojunction bipolar transistor (HBT) monolithic microwave integrated circuit (MMIC) technology. In order to optimize phase noise, the AIT and HNFF techniques are presented. The proposed VCO exhibited the phase noise of −117.3 dBc/Hz and −129.96 dBc/Hz...
This paper examines the sources of Receive Band Noise (RxBN) in the Envelope Tracking Power Amplifier (ETPA) system. The Envelope Amplifier (EA) nonlinearity is found to be the dominant cause. The output spectrum of the ETPA is compared for the cases of highly linear class-A EA and nonlinear EA. To improve the out-of-band noise performance of the ETPA, Digital Pre-Distortion (DPD) on the envelope...
The work presented in this paper aims to develop an optimized switch mode power amplifier (OSMPA) using existing techniques in sigma delta (ΣΔ) architecture that will lead to the design of low cost, low power consumption transceivers with flexible frequency transmission. This design will allow all digital tunability and eliminate the need for cascaded analog components. The implementation will improve...
A two-stage down-conversion architecture for 3.1–8 GHz ultra-wideband receiver front-end is designed which uses a local oscillator frequency equal to half the input frequency. The down-conversion technique is performed in two steps based on half-RF architecture to produce baseband signal. The proposed technique is implemented in 0.18 µm CMOS technology which achieves a conversion gain ranges from...
Direct conversion architectures have the advantage of no image frequencies, fewer components and lower cost. However local oscillator (LO) leakage reduces receive sensitivity, causes LO pulling, and is a challenging problem for direct conversion transceiver design. A mixer using the 2nd-order harmonic of LO is thus desired to address this issue. The sub-harmonic mixer, proposed in this paper, is based...
This article presents the design of a novel quad band LNA operating in the GSM 0.9GHz/GSM 1.8GHz and ZigBee 0.9GHz/WLAN 2.4GHz communication standards. This pseudo-concurrent architecture uses a one bit mode switch for selecting between the frequency bands. An RF switch is implemented before the Low Noise Amplifier (LNA) module to improve the insertion loss and isolation between the frequency bands...
Most published research related to RF switch-mode amplifiers has used sigma-delta modulation techniques to generate encoded pulse trains for amplification in the switching stage. A constraint in sigma-delta modulation is that zero-crossings are restricted to occur synchronously with a clock edge in the quantizer. In this paper, the zero crossing constraint is relaxed and a new encoder is analyzed...
This article presents the design of a novel quad-band LNA operating in the GSM 0.9GHz/GSM 1.8GHz and ZigBee 0.9GHz/WLAN 2.4GHz communication standards. This pseudo-concurrent architecture uses a two bit mode switch for selecting between the frequency bands. An RF switch is implemented before the Low Noise Amplifier (LNA) module to improve the insertion loss and isolation between the frequency bands...
The cellular mobile terminals continue to evolve at a rapid pace from voice phones to Multi-band, Multi standard Multi-media devices of the future. The RF front end, of these devices continues to be more complex requiring many RF bands and Wireless standards to be supported in a single device. In addition, to support higher data rates multiple antennas and passive filters are required. Concurrency...
Architectural and circuit techniques to integrate the RF front-end passive components, namely the SAW filters and duplexers that are traditionally implemented off chip, are presented. Intended for software defined radios, tunable high-Q filters allow the integration of highly reconfigurable transceiver front-ends that are robust to in-band and out-of-band blockers. Furthermore, duplexer techniques...
Using saturated power amplifier (PA) as the last stage, polar transmitter has the potential to be the most power efficient architecture to transmit large Peak-to-Average Ratio (PAR) signals. In this work, a polar transmitter using H-Bridge configured Class-D amplifiers is proposed. To fully exploit low voltage resource, maintain linearity and meet the spectrum mask requirements, RF Sigma-Delta Modulation...
A single-pole double-throw novel switch device in 0.18 ??m SOI complementary metal-oxide semiconductor (CMOS) process is developed for 0.9 Ghz wireless GSM systems. The layout of the device is optimized keeping in mind the parameters of interest for the RF switch. A subcircuit model, with the standard surface potential (PSP) model as the intrinsic FET model along with the parasitic elements is built...
High-speed T/R converter is developed in this paper by using the combination of the circulator, the limiter and the RF switch technology. The super low noise receiving technology is realized through reducing the transmission loss and improving the gain of LNA. Experiments have proved that the T/R component's power tolerance in this paper is more than 100 W, and that the blind distance caused by it...
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