The fifth-generation(5G)wireless technology is the most recent standardization in communication services of interest across the globe.The concept of Multiple-Input-Multiple-Output antenna(MIMO)systems has recently bee...The fifth-generation(5G)wireless technology is the most recent standardization in communication services of interest across the globe.The concept of Multiple-Input-Multiple-Output antenna(MIMO)systems has recently been incorporated to operate at higher frequencies without limitations.This paper addresses,design of a high-gain MIMO antenna that offers a bandwidth of 400 MHz and 2.58 GHz by resonating at 28 and 38 GHz,respectively for 5G millimeter(mm)-wave applications.The proposed design is developed on a RT Duroid 5880 substrate with a single elemental dimension of 9.53×7.85×0.8 mm^(3).The patch antenna is fully grounded and is fed with a 50-ohm stepped impedance microstrip line.It also has an I-shaped slot and two electromagnetically coupled parasitic slotted components.This design is initially constructed as a single-element structure and proceeded to a six-element MIMO antenna configuration with overall dimensions of 50×35×0.8 mm^(3).The simulated prototype is fabricated and measured for analyzing its performance characteristics,along with MIMO antenna diversity performance factors making the proposed antenna suitable for 5G mm-wave and 5G-operated handheld devices.展开更多
The problem of robustness-supported user association and small cell station(SCS) switching ON/OFF strategies in 5G millimeter wave(mm-wave) networks is investigated, where the robustness of access links is ensured and...The problem of robustness-supported user association and small cell station(SCS) switching ON/OFF strategies in 5G millimeter wave(mm-wave) networks is investigated, where the robustness of access links is ensured and the number of active SCSs is minimized for the reduction of the aggregation power consumption. Firstly, the problem is formulated as an integer programming(IP) problem. Then the problem is proved as a NP-hard problem by means of the simplification into the minimum dominant set(MDS), which is a NP-hard problem and is intractable to be solved in polynomial time. Secondly, a greedy-idea-based heuristic algorithm(GIHA) is proposed under the consideration of the complexity of the original optimization problem. Finally, superiorities of GIHA are demonstrated with the extensive simulations in 60 GHz mm-wave ultra-dense network in terms of access robustness and aggregate power consumption.展开更多
This paper discusses some challenges in the design of millimeter-wave(nunwave) circuits and systems for 5th generation(5G) wireless systems in CMOS process.The properties of some passive and active devices such as ind...This paper discusses some challenges in the design of millimeter-wave(nunwave) circuits and systems for 5th generation(5G) wireless systems in CMOS process.The properties of some passive and active devices such as inductors,capacitors,transmission lines,transformers and transistors in mm-wave frequency band are discussed.Self-healing technique dealing with PVT variation,resonant mode switching technique to enhance frequency tuning range of voltage controlled oscillator(VCO) and dual mode technique for power amplifier(PA) efficiency enhancement are introduced.At last,A fully-integrated60 GHz 5 Gb/s QPSK transceiver with the transmit/receive(T/R) switch in 65 nm CMOS process is introduced.The measured error vector magnitude(EVM) of the TX is-21.9dB while the bit error rate(BER) of the RX with a-52 dBm sine-wave input is below 8e-7when transmitting/receiving 5 Gb/s data.The transceiver is powered by 1.0 V and 1.2 V supply(except the phase-frequency detector and charge-pump in the frequency synthesizer which are powered by 2.5 V supply) and consumes 135 mW in TX mode and 176 mW in RX mode.展开更多
Coplanar waveguides （CPW） are widely used in mm-wave circuits designs for their good performance. A novel unified model of various on chip CPWs for mm-wave application, together with corresponding direct parameter e...Coplanar waveguides （CPW） are widely used in mm-wave circuits designs for their good performance. A novel unified model of various on chip CPWs for mm-wave application, together with corresponding direct parameter extraction methodologies, are proposed and investigated, where standard CPW, grounded CPW （GCPW） and CPW with slotted shield （SCPW） are included. Several kinds of influences of different structures are analyzed and considered into the model to explain the frequency-dependent per-unit-length L, C, R, and G parameters, among which the electromagnetic coupling for CPWs with large lower ground or shield is described by a new C-L-R series path in the parallel branch. The direct extraction procedures are established, which can ensure both accuracy and simplicity compared with other reported methods. Different CPWs are fabricated and measured on 90-nm CMOS processes with Short-Open-Load-Through （SOLT） de-embedding techniques. Excellent agreement between the model and the measured data for different CPWs is achieved up to 67 GHz.展开更多
In this paper, we propose a scheme for the generation of low phase noise tunable mm-wave signal by bearing two lightwaves in a photodiode. These two lightwaves are made phase coherent by an optoelectronic phase locked...In this paper, we propose a scheme for the generation of low phase noise tunable mm-wave signal by bearing two lightwaves in a photodiode. These two lightwaves are made phase coherent by an optoelectronic phase locked loop. Calculated mm-wave power at a frequency of 60 GHz is found to be -4 dBm.展开更多
We propose and experimentally validate an optical true time delay beamforming scheme with straightforward integration into hybrid optical/millimeter（mm）-wave access networks. In the proposed approach, the most compl...We propose and experimentally validate an optical true time delay beamforming scheme with straightforward integration into hybrid optical/millimeter（mm）-wave access networks. In the proposed approach, the most complex functions, including the beamforming network, are implemented in a central office, reducing the complexity and cost of remote antenna units. Different cores in a multi-core fiber are used to distribute the modulated signals to high-speed photodetectors acting as heterodyne mixers. The mm-wave carrier frequency is fixed to 50 GHz（VBand）, thereby imposing a progressive delay between antenna elements of a few picoseconds. That true time delay is achieved with an accuracy lower than 1 ps and low phase noise.展开更多
The challenges in the design of CMOS millimeter-wave （mm-wave） transceiver for Gbps wireless com- munication are discussed. To support the Gbps data rate, the link bandwidth of the receiver/transmitter must be wide ...The challenges in the design of CMOS millimeter-wave （mm-wave） transceiver for Gbps wireless com- munication are discussed. To support the Gbps data rate, the link bandwidth of the receiver/transmitter must be wide enough, which puts a lot of pressure on the mm-wave front-end as well as on the baseband circuit. This paper discusses the effects of the limited link bandwidth on the transceiver system performance and overviews the band- width expansion techniques for mm-wave amplifiers and IF programmable gain amplifier. Furthermore, dual-mode power amplifier （PA） and self-healing technique are introduced to improve the PA＇s average efficiency and to deal with the process, voltage, and temperature variation issue, respectively. Several fully-integrated CMOS mm-wave transceivers are also presented to give a short overview on the state-of-the-art mm-wave transceivers.展开更多
Millimeter wave(mm-wave)communication is widely considered to be a promising technique for 5G(Fifth Generation)cellular systems.Owing to the high path loss of mm-wave channels,5G networks could employ a heterogeneous ...Millimeter wave(mm-wave)communication is widely considered to be a promising technique for 5G(Fifth Generation)cellular systems.Owing to the high path loss of mm-wave channels,5G networks could employ a heterogeneous structure that consists of an MBS(Macro Base Station)and numerous SBSs(Small Base Stations).In this paper,we analyze the coverage and rate performance of an mm-wave heterogeneous network.Using user beam selection,we derive analytical expressions for the coverage probabilities of the SBSs and MBS.Furthermore,the average achievable rate for a typical user is also investigated.It is shown that the analytical results closely follow those of the simulations with marginal differences.展开更多
文摘The fifth-generation(5G)wireless technology is the most recent standardization in communication services of interest across the globe.The concept of Multiple-Input-Multiple-Output antenna(MIMO)systems has recently been incorporated to operate at higher frequencies without limitations.This paper addresses,design of a high-gain MIMO antenna that offers a bandwidth of 400 MHz and 2.58 GHz by resonating at 28 and 38 GHz,respectively for 5G millimeter(mm)-wave applications.The proposed design is developed on a RT Duroid 5880 substrate with a single elemental dimension of 9.53×7.85×0.8 mm^(3).The patch antenna is fully grounded and is fed with a 50-ohm stepped impedance microstrip line.It also has an I-shaped slot and two electromagnetically coupled parasitic slotted components.This design is initially constructed as a single-element structure and proceeded to a six-element MIMO antenna configuration with overall dimensions of 50×35×0.8 mm^(3).The simulated prototype is fabricated and measured for analyzing its performance characteristics,along with MIMO antenna diversity performance factors making the proposed antenna suitable for 5G mm-wave and 5G-operated handheld devices.
基金Supported by the National Natural Science Foundations of China(No.61771392,61771390,61871322,61501373,61271279)the National High Tochnology Research and Development Program of China(No.2014AA01A707,2015AA01A704)the Science and Technology on Avionics Integration Laboratory(No.20185553035)。
文摘The problem of robustness-supported user association and small cell station(SCS) switching ON/OFF strategies in 5G millimeter wave(mm-wave) networks is investigated, where the robustness of access links is ensured and the number of active SCSs is minimized for the reduction of the aggregation power consumption. Firstly, the problem is formulated as an integer programming(IP) problem. Then the problem is proved as a NP-hard problem by means of the simplification into the minimum dominant set(MDS), which is a NP-hard problem and is intractable to be solved in polynomial time. Secondly, a greedy-idea-based heuristic algorithm(GIHA) is proposed under the consideration of the complexity of the original optimization problem. Finally, superiorities of GIHA are demonstrated with the extensive simulations in 60 GHz mm-wave ultra-dense network in terms of access robustness and aggregate power consumption.
基金supported in part by the National Natural Science Foundation of China under Grant 61331003 and Grant 61222405
文摘This paper discusses some challenges in the design of millimeter-wave(nunwave) circuits and systems for 5th generation(5G) wireless systems in CMOS process.The properties of some passive and active devices such as inductors,capacitors,transmission lines,transformers and transistors in mm-wave frequency band are discussed.Self-healing technique dealing with PVT variation,resonant mode switching technique to enhance frequency tuning range of voltage controlled oscillator(VCO) and dual mode technique for power amplifier(PA) efficiency enhancement are introduced.At last,A fully-integrated60 GHz 5 Gb/s QPSK transceiver with the transmit/receive(T/R) switch in 65 nm CMOS process is introduced.The measured error vector magnitude(EVM) of the TX is-21.9dB while the bit error rate(BER) of the RX with a-52 dBm sine-wave input is below 8e-7when transmitting/receiving 5 Gb/s data.The transceiver is powered by 1.0 V and 1.2 V supply(except the phase-frequency detector and charge-pump in the frequency synthesizer which are powered by 2.5 V supply) and consumes 135 mW in TX mode and 176 mW in RX mode.
基金Project supported by the State Key Development Program for Basic Research of China(No.2010CB327404)the National High Technology Research and Development Program of China(No.2011AA010202)+2 种基金the National Science and Technology Major Project of China(No.2012ZX03004004)the National Natural Science Foundation of China(Nos.61176034,61101001,61204026)the Tsinghua University Initiative Scientific Research Program
文摘Coplanar waveguides （CPW） are widely used in mm-wave circuits designs for their good performance. A novel unified model of various on chip CPWs for mm-wave application, together with corresponding direct parameter extraction methodologies, are proposed and investigated, where standard CPW, grounded CPW （GCPW） and CPW with slotted shield （SCPW） are included. Several kinds of influences of different structures are analyzed and considered into the model to explain the frequency-dependent per-unit-length L, C, R, and G parameters, among which the electromagnetic coupling for CPWs with large lower ground or shield is described by a new C-L-R series path in the parallel branch. The direct extraction procedures are established, which can ensure both accuracy and simplicity compared with other reported methods. Different CPWs are fabricated and measured on 90-nm CMOS processes with Short-Open-Load-Through （SOLT） de-embedding techniques. Excellent agreement between the model and the measured data for different CPWs is achieved up to 67 GHz.
文摘In this paper, we propose a scheme for the generation of low phase noise tunable mm-wave signal by bearing two lightwaves in a photodiode. These two lightwaves are made phase coherent by an optoelectronic phase locked loop. Calculated mm-wave power at a frequency of 60 GHz is found to be -4 dBm.
基金founded by H2020 ITN CELTA under Grant No.675683 of Call:H2020-MSCA-ITN-2015
文摘We propose and experimentally validate an optical true time delay beamforming scheme with straightforward integration into hybrid optical/millimeter（mm）-wave access networks. In the proposed approach, the most complex functions, including the beamforming network, are implemented in a central office, reducing the complexity and cost of remote antenna units. Different cores in a multi-core fiber are used to distribute the modulated signals to high-speed photodetectors acting as heterodyne mixers. The mm-wave carrier frequency is fixed to 50 GHz（VBand）, thereby imposing a progressive delay between antenna elements of a few picoseconds. That true time delay is achieved with an accuracy lower than 1 ps and low phase noise.
基金Project supported in part by the National Natural Science Foundation of China(No.61331003)
文摘The challenges in the design of CMOS millimeter-wave （mm-wave） transceiver for Gbps wireless com- munication are discussed. To support the Gbps data rate, the link bandwidth of the receiver/transmitter must be wide enough, which puts a lot of pressure on the mm-wave front-end as well as on the baseband circuit. This paper discusses the effects of the limited link bandwidth on the transceiver system performance and overviews the band- width expansion techniques for mm-wave amplifiers and IF programmable gain amplifier. Furthermore, dual-mode power amplifier （PA） and self-healing technique are introduced to improve the PA＇s average efficiency and to deal with the process, voltage, and temperature variation issue, respectively. Several fully-integrated CMOS mm-wave transceivers are also presented to give a short overview on the state-of-the-art mm-wave transceivers.
基金supported by the National Natural Science Foundation of China(Nos.61231011,61231013,and 61571025).
文摘Millimeter wave(mm-wave)communication is widely considered to be a promising technique for 5G(Fifth Generation)cellular systems.Owing to the high path loss of mm-wave channels,5G networks could employ a heterogeneous structure that consists of an MBS(Macro Base Station)and numerous SBSs(Small Base Stations).In this paper,we analyze the coverage and rate performance of an mm-wave heterogeneous network.Using user beam selection,we derive analytical expressions for the coverage probabilities of the SBSs and MBS.Furthermore,the average achievable rate for a typical user is also investigated.It is shown that the analytical results closely follow those of the simulations with marginal differences.
