Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8563459
S. Jang, Yung-Han Chang, W. Lai
This letter studies a feedback GaN HEMT oscillator implemented with the WIN $0.255{mu m}$ GaN HEMT technology. The oscillator consists of a HEMT amplifier with an LC feedback network. With the supply voltage of $text{V}_{text{DD}} =1.8 text{V}$, the GaN VCO current and power consumption of the oscillator are 10.18 mA and 18.33mW, respectively. The oscillator can generate single-ended signal at 7.26GHz and it also supplies output power 1.06 dBm. At 1MHz frequency offset from the carrier the phase noise is −122.48 dBc/Hz. The die area of the GaN HEMT oscillator is $2times 1 text{mm}^{2}$.
{"title":"A Feedback GaN HEMT Oscillator","authors":"S. Jang, Yung-Han Chang, W. Lai","doi":"10.1109/ICMMT.2018.8563459","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8563459","url":null,"abstract":"This letter studies a feedback GaN HEMT oscillator implemented with the WIN $0.255{mu m}$ GaN HEMT technology. The oscillator consists of a HEMT amplifier with an LC feedback network. With the supply voltage of $text{V}_{text{DD}} =1.8 text{V}$, the GaN VCO current and power consumption of the oscillator are 10.18 mA and 18.33mW, respectively. The oscillator can generate single-ended signal at 7.26GHz and it also supplies output power 1.06 dBm. At 1MHz frequency offset from the carrier the phase noise is −122.48 dBc/Hz. The die area of the GaN HEMT oscillator is $2times 1 text{mm}^{2}$.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126959158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8563437
Shen Xu, Xiaokang Tian, Lili Xu
In this paper, a four-way broadband power divider operating from S-band to Ku-band (2GHz-18GHz) is presented and demonstrated. Compared with conventional simple T-shaped power divider, this power divider applies multi-section impedance transformers and suspended microstrip line(SSML) in order to achieve the average insertion loss about -6.3dB and the return loss less than -15dB. In addition, this power divider is adopted in a nonresonante chained structure so that its outputs can theoretically be arbitrary $pmb{2}^{mathbf{N}}$ ways. The simulated return loss is fully less than -15dB in the whole band, while it is also less than -20dB from 4.43GHz to 18GHz. And simulated insertion loss is near -6.3dB. The final measured results shows a good agreement with simulated results.
{"title":"A 4-Way Broadband Power Divider Based on the Suspended Microstrip Line","authors":"Shen Xu, Xiaokang Tian, Lili Xu","doi":"10.1109/ICMMT.2018.8563437","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8563437","url":null,"abstract":"In this paper, a four-way broadband power divider operating from S-band to Ku-band (2GHz-18GHz) is presented and demonstrated. Compared with conventional simple T-shaped power divider, this power divider applies multi-section impedance transformers and suspended microstrip line(SSML) in order to achieve the average insertion loss about -6.3dB and the return loss less than -15dB. In addition, this power divider is adopted in a nonresonante chained structure so that its outputs can theoretically be arbitrary $pmb{2}^{mathbf{N}}$ ways. The simulated return loss is fully less than -15dB in the whole band, while it is also less than -20dB from 4.43GHz to 18GHz. And simulated insertion loss is near -6.3dB. The final measured results shows a good agreement with simulated results.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132689437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8563282
Xiangyu Zhou, J. Shi, Dan Feng, H. Zhai
A low-profile dual-polarized MIMO antenna array with high isolation is proposed in this paper. As is shown in this paper, the unit of the presented MIMO antenna array is two crossed dipole antennas. The height of the dipole antenna is just 10mm. It is a low profile because of the application of the AMC surface. As a result, the proposed MIMO antenna array can offer an impedance band from 2.50 GHz to 2.68 GHz when the VSWR is lower than 1.5. At the same time, The MIMO antenna array also presents great performance in radiation patterns, with the gain of 9dBi and the isolation between the two ports can reach 25dB. The proposed MIMO antenna array can be applied to the base stations.
{"title":"A Low-Profile Dual-Polarized MIMO Antenna Array with High Isolation","authors":"Xiangyu Zhou, J. Shi, Dan Feng, H. Zhai","doi":"10.1109/ICMMT.2018.8563282","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8563282","url":null,"abstract":"A low-profile dual-polarized MIMO antenna array with high isolation is proposed in this paper. As is shown in this paper, the unit of the presented MIMO antenna array is two crossed dipole antennas. The height of the dipole antenna is just 10mm. It is a low profile because of the application of the AMC surface. As a result, the proposed MIMO antenna array can offer an impedance band from 2.50 GHz to 2.68 GHz when the VSWR is lower than 1.5. At the same time, The MIMO antenna array also presents great performance in radiation patterns, with the gain of 9dBi and the isolation between the two ports can reach 25dB. The proposed MIMO antenna array can be applied to the base stations.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132948594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8563658
X. Sun, Yuanjian Liu, Shuangde Li
Based on shooting and bouncing ray tracing/image method (SBR/IM), millimeter wave (mmWave) propagation characteristics was simulated and analyzed inside a bus at 60 GHz. The statistical analysis of simulation results considering large scale fading and delay parameters has been performed, such as path loss and root mean square (RMS) delay spread obtained for some fixed positions in the bus, providing good agreement with statistics for known literature. In addition, the path loss of the aisle and the received power of the whole intra-vehicle are simulated and analyzed. This study, which provides a theoretical basis for simplifying the millimeter wave propagation model in intra-vehicle, is conductive to the network planning and optimization of wireless communication within the vehicle, and lays the foundation for the future development of the fifth generation mobile communication technology.
{"title":"Study on 60 GHz Millimeter Wave Propagation Characteristics Inside a Bus Based on SBR/IM Method","authors":"X. Sun, Yuanjian Liu, Shuangde Li","doi":"10.1109/ICMMT.2018.8563658","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8563658","url":null,"abstract":"Based on shooting and bouncing ray tracing/image method (SBR/IM), millimeter wave (mmWave) propagation characteristics was simulated and analyzed inside a bus at 60 GHz. The statistical analysis of simulation results considering large scale fading and delay parameters has been performed, such as path loss and root mean square (RMS) delay spread obtained for some fixed positions in the bus, providing good agreement with statistics for known literature. In addition, the path loss of the aisle and the received power of the whole intra-vehicle are simulated and analyzed. This study, which provides a theoretical basis for simplifying the millimeter wave propagation model in intra-vehicle, is conductive to the network planning and optimization of wireless communication within the vehicle, and lays the foundation for the future development of the fifth generation mobile communication technology.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131343152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8563785
Hao Wang, Zhongtian Ye, Jianyin Cao, Yan Wang, Rong Gao
A W-band magneto-electric (ME) dipole antenna array using a low-loss double-sided gap waveguide (DSGWG) feed network is presented with high gain and wide band performance. The ME dipole antenna element is composed of a DSGWG open slot radiating as an equivalent magnetic dipole and pairs of metallic pins working as electric dipoles. The feed network is composed of DSGWG power dividers, which could reduce transmission loss and improve antenna gain. The simulated results show that the antenna element achieves a gain over 8 dBi from 83 GHz to 115 GHz, and the gain fluctuation is below 3 dB. The $1times 4$ ME antenna array is also designed with a gain up to 14.8 dBi by reconfiguring ME dipole antenna elements and the feed network.
{"title":"W-band High-Gain Magneto-Electric Dipole Antenna Array with Double-Sided Gap Waveguide Feed Network","authors":"Hao Wang, Zhongtian Ye, Jianyin Cao, Yan Wang, Rong Gao","doi":"10.1109/ICMMT.2018.8563785","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8563785","url":null,"abstract":"A W-band magneto-electric (ME) dipole antenna array using a low-loss double-sided gap waveguide (DSGWG) feed network is presented with high gain and wide band performance. The ME dipole antenna element is composed of a DSGWG open slot radiating as an equivalent magnetic dipole and pairs of metallic pins working as electric dipoles. The feed network is composed of DSGWG power dividers, which could reduce transmission loss and improve antenna gain. The simulated results show that the antenna element achieves a gain over 8 dBi from 83 GHz to 115 GHz, and the gain fluctuation is below 3 dB. The $1times 4$ ME antenna array is also designed with a gain up to 14.8 dBi by reconfiguring ME dipole antenna elements and the feed network.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"189 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114853197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8563329
Shun‐Hui Zhu, Xue‐Song Yang, Jian Wang, Bingzhong Wang
Material distribution method, which is a topology optimization algorithm, is used to design the isolation structure in a MIMO antenna. This topology optimization algorithm has the advantage of high topology optimization ability. It is utilized to optimize the impedance matching, port-to-port isolation and polarization of the MIMO antenna. The optimized antenna is verified by HFSS simulation. At the anticipated operation frequency of 5.8 GHz, the return loss is -25 dB, and the mutual coupling between the two ports is -30 dB. That means, in the case of center-to-center distance of $pmb{sim 0.39} lambda_{0}$, a reduction of more than 17 dB in mutual coupling is achieved. Besides, the relative cross-polarization ratio is 18 dB. We can see this method can be applied in the optimization of MIMO antennas.
{"title":"Design of MIMO Antenna Isolation Structure by Material Distribution Method Optimization","authors":"Shun‐Hui Zhu, Xue‐Song Yang, Jian Wang, Bingzhong Wang","doi":"10.1109/ICMMT.2018.8563329","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8563329","url":null,"abstract":"Material distribution method, which is a topology optimization algorithm, is used to design the isolation structure in a MIMO antenna. This topology optimization algorithm has the advantage of high topology optimization ability. It is utilized to optimize the impedance matching, port-to-port isolation and polarization of the MIMO antenna. The optimized antenna is verified by HFSS simulation. At the anticipated operation frequency of 5.8 GHz, the return loss is -25 dB, and the mutual coupling between the two ports is -30 dB. That means, in the case of center-to-center distance of $pmb{sim 0.39} lambda_{0}$, a reduction of more than 17 dB in mutual coupling is achieved. Besides, the relative cross-polarization ratio is 18 dB. We can see this method can be applied in the optimization of MIMO antennas.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"341 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134138299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8563348
Li Guo, M. Tang
In this paper, a low-profile dual-linear polarized patch antenna composed of two stacked substrates, one air gap layer, and one grounded substrate is proposed. There is a feeding patch element with two excited probes placed on the top side of the grounded substrate, and one parasitic patch element and a 2×2 parasitic array patch elements printed on the lower and upper stacked substrate, respectively. The T- and rectangular slots and T-stubs are employed on/near the orthogonal axis of the patches for the impedance matching and two orthogonal polarizations improvement. Furthermore, four stacked complementary split-ring resonators (CSRRs) are loaded in the two stacked substrates mainly to adjust the impedance matching and port isolation with an induced dual-polarized resonance. Thanks to the stacked patches and CSRRs, an enhanced impedance bandwidth from 1.2% to 7.4% was achieved by the introduced three additional dual-polarized resonances. Simulated results show the antenna has a impedance bandwidth across 2.362-2.544 GHz (fractional bandwidth 7.4%), a maximum realized gain of 10 dBi, and port isolation better than 22 dB over the operational bandwidth. In addition, a low profile of 0.048λo (where λ0is the free-space wavelength at the central frequency) is maintained in the proposed antenna.
{"title":"A Low-Profile Dual-Polarized Patch Antenna with Bandwidth Enhanced by Stacked Parasitic Elements","authors":"Li Guo, M. Tang","doi":"10.1109/ICMMT.2018.8563348","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8563348","url":null,"abstract":"In this paper, a low-profile dual-linear polarized patch antenna composed of two stacked substrates, one air gap layer, and one grounded substrate is proposed. There is a feeding patch element with two excited probes placed on the top side of the grounded substrate, and one parasitic patch element and a 2×2 parasitic array patch elements printed on the lower and upper stacked substrate, respectively. The T- and rectangular slots and T-stubs are employed on/near the orthogonal axis of the patches for the impedance matching and two orthogonal polarizations improvement. Furthermore, four stacked complementary split-ring resonators (CSRRs) are loaded in the two stacked substrates mainly to adjust the impedance matching and port isolation with an induced dual-polarized resonance. Thanks to the stacked patches and CSRRs, an enhanced impedance bandwidth from 1.2% to 7.4% was achieved by the introduced three additional dual-polarized resonances. Simulated results show the antenna has a impedance bandwidth across 2.362-2.544 GHz (fractional bandwidth 7.4%), a maximum realized gain of 10 dBi, and port isolation better than 22 dB over the operational bandwidth. In addition, a low profile of 0.048λo (where λ0is the free-space wavelength at the central frequency) is maintained in the proposed antenna.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132749837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8564005
Guangyu Hu, Chao Yu, Xiaowei Zhu
In this paper, a comparative study of different digital predistortion models is presented in the scenario of a phased array transmitter with multi-channel time delay in the over-the-air (OTA) feedback loop-based structure. The performance for three classic volterra models with enhanced piecewise technique is compared. Experiment results indicated that all the models above can be applied to this scenario and achieve satisfactory linearization performance.
{"title":"Digital Predistortion Model Comparison for Phased Array Transmitters with Multi-Channel Time Delay","authors":"Guangyu Hu, Chao Yu, Xiaowei Zhu","doi":"10.1109/ICMMT.2018.8564005","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8564005","url":null,"abstract":"In this paper, a comparative study of different digital predistortion models is presented in the scenario of a phased array transmitter with multi-channel time delay in the over-the-air (OTA) feedback loop-based structure. The performance for three classic volterra models with enhanced piecewise technique is compared. Experiment results indicated that all the models above can be applied to this scenario and achieve satisfactory linearization performance.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133457444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8563697
Li Yuchao, Zhong Shichang, Lu Wei
This paper presents a new GaN broadband and internally matched power amplifier. The coexistent technology of L-section multisession transformer and negative feedback is used. Using one 3.6 mm power GaN HEMT die, made by Nanjing Electronic Devices Institute. The amplifier demons rates an output power of more than 40dBm with a power gain of over 12.5 dB and relative wideband of 148% and the typical PAE of 40% across the band of 0.3-2.0GHz.
{"title":"Design of a Broadband GaN Power Amplifier","authors":"Li Yuchao, Zhong Shichang, Lu Wei","doi":"10.1109/ICMMT.2018.8563697","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8563697","url":null,"abstract":"This paper presents a new GaN broadband and internally matched power amplifier. The coexistent technology of L-section multisession transformer and negative feedback is used. Using one 3.6 mm power GaN HEMT die, made by Nanjing Electronic Devices Institute. The amplifier demons rates an output power of more than 40dBm with a power gain of over 12.5 dB and relative wideband of 148% and the typical PAE of 40% across the band of 0.3-2.0GHz.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130553984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-07DOI: 10.1109/ICMMT.2018.8563794
Chong Guo, Chang Shu, F. Huang, Tao Sun, Ling Tian, W. Hong
The design and implementation of a highly integrated and reliable single board 8-channel transceiver at 3.5GHz is developed for massive MIMO system in 5G wireless communications. Based on this board, large scale 2D arrays, such as ${8text{x}8}$ array, can be easily formed. On each board, 8 transmitting channels and 8 receiving channels in TDD mode are integrated and each Tx/Rx channel shares one antenna element. This transceiver can provide a verification platform for digital beamforming algorithm.
{"title":"Design and Implementation of a Highly Integrated 8-Channel Transceiver for Massive MIMO in 5G","authors":"Chong Guo, Chang Shu, F. Huang, Tao Sun, Ling Tian, W. Hong","doi":"10.1109/ICMMT.2018.8563794","DOIUrl":"https://doi.org/10.1109/ICMMT.2018.8563794","url":null,"abstract":"The design and implementation of a highly integrated and reliable single board 8-channel transceiver at 3.5GHz is developed for massive MIMO system in 5G wireless communications. Based on this board, large scale 2D arrays, such as ${8text{x}8}$ array, can be easily formed. On each board, 8 transmitting channels and 8 receiving channels in TDD mode are integrated and each Tx/Rx channel shares one antenna element. This transceiver can provide a verification platform for digital beamforming algorithm.","PeriodicalId":190601,"journal":{"name":"2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125889444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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