Multi-frequency point supported LLRF front-end for CiADS wide-bandwidth application

The China initiative Accelerator Driven System,CiADS,physics design adopts 162.5 MHz,325 MHz,and 650 MHz cavities,which are driven by the corresponding radio frequency(RF)power system,requiring frequency translation front-end for the RF station.For that application,a general-purpose design front-end prototype has been developed to evaluate the multi-frequency point supported design feasibility.The difficult parts to achieve the requirements of the general-purpose design are reasonable device selection and balanced design.With a carefully selected low-noise wide-band RF mixer and amplifier to balance the performance of multi-frequency supported down-conversion,specially designed LO distribution net to increase isolation between adjacent channels,and external band-pass filter to realize expected up-conversion frequencies,high maintenance and modular front-end generalpurpose design has been implemented.Results of standard parameters show an R2 value of at least 99.991%in the range of-60-10 dBm for linearity,up to 18 dBm for P1dB,and up to 89 dBc for cross talk between adjacent channels.The phase noise spectrum is lower than 80 dBc in the range of 0-1 MHz;cumulative phase noise is 0.006°;and amplitude and phase stability are 0.022%and 0.034°,respectively.

Advances in Digital Front-End and Software RF Processing: PartⅡ

In the first editorial of this two-part special issue, we pointed out that one of the biggest trends in wireless broadband, radar, sonar, and broadcasting technology is software RF processing and digital front-end [1]. Thistrend encompasses signal processing algorithms and integrated circuit design and includes digital pre-distortion （DPD）, conversions between digital and analog signals, digita up-conversion （DUC）, digital down-conversion （DDC）, DC offset,

Advances in Digital Front-End and Software RF Processing:Part I

One of the biggest technology trends in wireless broadband, radar, sonar, and broadcasting systems is software radio frequency processing and digital front-end. This trend encompasses a broad range of topics, from circuit design and signal processing to system integration. It includes digital up-conversion （DUC） and down-conversion （DDC）, digital predistortion （DPD）,

A tunable passive mixer for SAW-less front-end with reconfigurable voltage conversion gain and intermediate frequency bandwidth

An adjustable mixer for surface acoustic wave( SAW)-less radio frequency( RF) front-end is presented in this paper. Through changing the bias voltage,the presented mixer with reconfigurable voltage conversion gain( VCG) is suitable for multi-mode multi-standard( MMMS) applications. An equivalent local oscillator( LO) frequency-tunable high-Q band-pass filter( BPF) at low noise amplifier( LNA) output is used to reject the out-of-band interference signals. Base-band( BB) capacitor of the mixer is variable to obtain 15 kinds of intermediate frequency( IF) bandwidth( BW). The proposed passive mixer with LNA is implemented in TSMC 0. 18μm RF CMOS process and operates from 0. 5 to 2. 5 GHz with measured maximum out-of-band rejection larger than 40 d B. The measured VCG of the front-end can be changed from 5 to 17 d B; the maximum input intercept point( IIP3) is0 d Bm and the minimum noise figure( NF) is 3. 7 d B. The chip occupies an area of 0. 44 mm^2 including pads.

一种3.5 GHz频段双通道射频前端设计

随着5G商用网络的快速建设,国内5G网络测试设备存在大量空缺。为此,设计了一种适用于5G终端模拟器的3.5 GHz频段双通道射频前端。该射频前端结合了ADRV9009芯片,可同时支持双通道收发,具有器件数少、设计复杂度低的特点。实测结果表明,该射频前端性能稳定,接收灵敏度为-85 d Bm,噪声系数小于2.6 dB,256QAM调制下发射信号的误差矢量幅度为1.43%,达到了5G终端模拟器的设计要求。

An RF front-end with an automatic gain control technique for a U/V band CMMB receiver

This paper presents a fully integrated RF front-end with an automatic gain control（AGC） scheme and a digitally controlled radio frequency varied gain amplifier（RFVGA） for a U/V band China Mobile Multimedia Broadcasting（CMMB） direct conversion receiver.The RFVGA provides a gain range of 50 dB with a 1.6 dB step. The adopted AGC strategy could improve immunity to adjacent channel signal,which is of importance for CMMB application.The front-end,composed of a low noise amplifier（LNA）,an RFVGA,a mixer and AGC,achieves an input referred 3rd order intercept point（IIP3） of 4.9 dBm with the LNA in low gain mode and the RFVGA in medium gain mode,and a less than 4 dB double side band noise figure with both the LNA and the RFVGA in high gain mode.The proposed RF front-end is fabricated in a 0.35μm SiGe BiCMOS technology and consumes 25.6 mA from a 3.0 V power supply.

A wideband large dynamic range and high linearity RF front-end for U-band mobile DTV

A wideband large dynamic range and high linearity U-band RF front-end for mobile DTV is introduced, and includes a noise-cancelling low-noise amplifier （LNA）, an RF programmable gain amplifier （RFPGA） and a current communicating passive mixer. The noise/distortion cancelling structure and RC post-distortion compensation are employed to improve the linearity of the LNA. An RFPGA with five stages provides large dynamic range and fine gain resolution. A simple resistor voltage network in the passive mixer decreases the gate bias voltage of the mixing transistor, and optimum linearity and symmetrical mixing is obtained at the same time. The RF front-end is implemented in a 0.25 #m CMOS process. Tests show that it achieves an IIP3 （third-order intercept point） of -17 dBm, a conversion gain of 39 dB, and a noise figure of 5.8 dB. The RFPGA achieves a dynamic range of-36.2 to 23.5 dB with a resolution of 0.32 dB.

Noise-canceling and IP3 improved CMOS RF front-end for DRM/DAB/DVB-H applications

A CMOS RF（radio frequency） front-end for digital radio broadcasting applications is presented that contains a wideband LNA,I/Q-mixers and VGAs,supporting other various wireless communication standards in the ultrawide frequency band from 200 kHz to 2 GHz as well.Improvement of the NF（noise figure） and IP3（third-order intermodulation distortion） is attained without significant degradation of other performances like voltage gain and power consumption.The NF is minimized by noise-canceling technology,and the IP3 is improved by using differential multiple gate transistors（DMGTR）.The dB-in-linear VGA（variable gain amplifier） exploits a single PMOS to achieve exponential gain control.The circuit is fabricated in 0.18-μm CMOS technology.The S11 of the RF front-end is lower than -11.4 dB over the whole band of 200 kHz-2 GHz.The variable gain range is 12-42 dB at 0.25 GHz and 4-36 dB at 2 GHz.The DSB NF at maximum gain is 3.1-6.1 dB.The IIP3 at middle gain is -4.7 to 0.2 dBm.It consumes a DC power of only 36 mW at 1.8 V supply.

A-3 dBm RF transmitter front-end for 802.11g application

A 2.4 GHz, direct-conversion RF transmitter front-end with an up converter and PA driver is fabricated in a 0.13/zm CMOS process for the reliable transmission of 54 Mb/s OFDM signals. The front-end output power is -3 dBm while the corresponding EVM is -27 dB which is necessary for the 802.11g standard of EVM at-25 dB. With the adopted gain control strategy the output power changes from -14.3 to -3.7 dBm with every step 0.8 dB （20%） which covers the gain variation due to working temperature and process. A power detector indicates the output power and delivers a voltage to the baseband to control the output power.

Design of a low-power 433/915-MHz RF front-end with a current-reuse common-gate LNA

This paper presents a wideband RF front-end with novel current-reuse wide band low noise amplifier （LNA）, current-reuse V-I converter, active double balanced mixer and transimpedance amplifier for short range device （SRD） applications. With the proposed current-reuse LNA, the DC consumption of the front-end reduces considerably while maintaining sufficient performance needed by SRD devices. The RF front-end was fabricated in 0.18μm RFCMOS process and occupies a silicon area of just 0.11 mm^2. Operating in 433 MHz band, the measurement results show the RF front-end achieves a conversion gain of 29.7 dB, a double side band noise figure of 9.7 dB, an input referenced third intercept point of -24.9 dBm with only 1.44 mA power consumption from 1.8 V supply. Compared to other reported front-ends, it has an advantage in power consumption.

A Compact 28 GHz Millimeter Wave Antenna for Future Wireless Communication

This article presents a novel modified chuck wagon dinner bell shaped millimeter wave(mm-wave)antenna at 28 GHz.The proposed design has ultra-thin Rogers 5880 substrate with relative permittivity of 2.2.The design consists of T shaped resonating elements and two open ended side stubs.The desired 28 GHz frequency response is achieved by careful parametric modeling of the proposed structure.The maximum achieved single element gain at the desired resonance frequency is 3.45 dBi.The efficiency of the proposed design over the operating band is more than 88%.The impedance bandwidth achieved for−10 dB reference value is nearly 2.9 GHz.The proposed antenna is transformed into four element linear array which increases the gain up to 10.5 dBi.The fabricated prototype is tested for the measured results.It is observed that measured results closely match the simulated results.By considering its simple structure and focused radiation patterns,the proposed design is well suited for IoT(Internet of Things),mmWave microwave sensing,5G and future RF(Radio Frequency)frontends.

A 1.2-V CMOS front-end for LTE direct conversion SAW-less receiver

A CMOS RF front-end for the long-term evolution（LTE） direct conversion receiver is presented.With a low noise transconductance amplifier（LNA）,current commutating passive mixer and transimpedance operational amplifier（TIA）,the RF front-end structure enables high-integration,high linearity and simple frequency planning for LTE multi-band applications.Large variable gain is achieved using current-steering transconductance stages.A current commutating passive mixer with 25%duty-cycle LO improves gain,noise and linearity.A direct coupled current-input filter（DCF） is employed to suppress the out-of-band interferer.Fabricated in a 0.13-μm CMOS process,the RF front-end achieves a 45 dB conversion voltage gain,2.7 dB NF,-7 dBm IIP3,and ＋60 dBm IIP2 with calibration from 2.3 to 2.7 GHz.The total RF front end with divider draws 40 mA from a single 1.2-V supply.

Quad-channel broadband compact multi-antenna GNSS down-converter for high-reliability navigation

A high-reliability broadband high-linearity down-converter for multi-antenna global navigation satellite system(GNSS)receiver is presented in this paper.Based on direction-of-arrival estimation,the multi-antenna GNSS receiver can separate the GNSS signals from the interfering signals and suppress harmful broadband radio frequency interferences.To drive the off-chip 50Ω2 resistive load and meet the stringent requirements of linearity,a quad-channel down-converter with a broadband common-gate low-noise transcon-ductance amplifier,current-driven passive mixer and novel bridge mode transimpedance driving amplifier have been proposed to contruct the multi-antenna recelver.The operating frequency of this down-converter is from 1.15 to 1.65 GHz,covering all bands for global positioning system(GPS),Beidou navigation satellite system(BDS),global navigation satellite system(GLONASS)and Galileo.The measured results show that the proposed quad-channel down-converter achieves+38 dBm output 3rd order intercept point(OIP3)and+17 dBm OP1dB(output-referred 1 dB compression point),9.5 dB to 12.9 dB noise figure(NF)across the variable gain of 10 dB to 27 dB and approximately 47 dB channel isolation.

Compact multilayer dual-band bandpass filter design using stepped impedance resonators

Compact dual-band bandpass filter(BPF)for the 5 th generation mobile communication technology(5 G)radio frequency(RF)front-end applications was presented based on multilayer stepped impedance resonators(SIRs).The multilayer dual-band SIR BPF can achieve high selectivity and four transmission zeros(TZs)near the passband edges by the quarter-wavelength tri-section SIRs.The multilayer dual-band SIR BPF is fabricated on a 3-layer FR-4 substrate with a compact dimension of 5.5 mm×5.0 mm×1.2 mm.The measured two passbands of the multilayer dual-band SIR BPF are 3.3 GHz-3.5 GHz and 4.8 GHz-5.0 GHz with insertion loss(IL)less than 2 dB respectively.Both measured and simulated results suggest that it is a possible candidate for the application of 5 G RF front-end at sub-6 GHz frequency band.