Pub Date : 2012-10-01DOI: 10.23919/EUMC.2012.6459301
Young-Sik Seo, Z. Hughes, D. Isom, M. Nguyen, S. Deb, S. Rao, J. Chiao
In this work, wireless power transfer issues were investigated for a gastroparesis management system consisting of an endoscopically-implantable miniature batteryless/rechargeable wireless gastrostimulator and a wearable battery-operated transmitter module. Output power for stimulation and input power consumption in the transmitter as well as the wireless power transfer efficiency of two coil antennas with significantly different sizes were examined. With an implant antenna coil of 1×3.5 cm2 and 5-cm radius transmitter antenna coils of varying coil turns, power transfers and efficiencies at the individually-tuned resonance of 1.3MHz were experimentally obtained at various coil separation distances from 4 to 10 cm between two coils. Taking power consumption in the wearable module and tolerance of parasitic capacitance in the environment into consideration, a 17-turn transmitter coil was chosen. RF losses through tissues were also examined with saline mimicking the abdomen tissues. At a distance of 10 cm as the worst scenario, a load current 3.02 mA was achieved which was still sufficient for gastrostimulation. Measurements of output voltage and efficiency distribution were mapped in 3-D to examine the effects of antenna misalignment due to body and stomach motion. This work provided insights into a complete system design for an endoscopically-implantable gastrostimulator that could relieve the suffering of many gastroparesis patients.
{"title":"Wireless power transfer for a miniature gastrostimulator","authors":"Young-Sik Seo, Z. Hughes, D. Isom, M. Nguyen, S. Deb, S. Rao, J. Chiao","doi":"10.23919/EUMC.2012.6459301","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459301","url":null,"abstract":"In this work, wireless power transfer issues were investigated for a gastroparesis management system consisting of an endoscopically-implantable miniature batteryless/rechargeable wireless gastrostimulator and a wearable battery-operated transmitter module. Output power for stimulation and input power consumption in the transmitter as well as the wireless power transfer efficiency of two coil antennas with significantly different sizes were examined. With an implant antenna coil of 1×3.5 cm2 and 5-cm radius transmitter antenna coils of varying coil turns, power transfers and efficiencies at the individually-tuned resonance of 1.3MHz were experimentally obtained at various coil separation distances from 4 to 10 cm between two coils. Taking power consumption in the wearable module and tolerance of parasitic capacitance in the environment into consideration, a 17-turn transmitter coil was chosen. RF losses through tissues were also examined with saline mimicking the abdomen tissues. At a distance of 10 cm as the worst scenario, a load current 3.02 mA was achieved which was still sufficient for gastrostimulation. Measurements of output voltage and efficiency distribution were mapped in 3-D to examine the effects of antenna misalignment due to body and stomach motion. This work provided insights into a complete system design for an endoscopically-implantable gastrostimulator that could relieve the suffering of many gastroparesis patients.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132241912","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 : 2012-10-01DOI: 10.23919/EUMC.2012.6459240
Po-Sheng Huang, Shuan-An Wei, Shan-Fon Hong, T. Lin, Pai-Yu Chen, Hsin-Chia Lu
Surface mount unit cells for phase leading bandpass networks are developed for easy integration with microstrip lines on PCB for the phase shifter implementation. With the suitable design of layout and fabricated in low temperature cofired ceramic (LTCC), the bandpass network and its parasitic components are controlled to ensure the broadband operation. These unit cells of phase leading bandpass networks are mounted with phase lag microstrip lines on PCB for the design of broadband phase shifters. Unit cells can be cascaded in a single branch of power divider to create large phase shift or placed at different branch to give small phase shift while keeping sufficient return loss bandwidth. Four phase shfiters with phase shift of 22.5°, 45°, 90° and 135° are fabricated and measured using three different unit cells. Measured results of all four phase shifters show about 100% phase shift bandwidth, better than 10 dB return loss and less than 1.4 dB imbalance from 2.6 to 7.7 GHz.
{"title":"Phase shifters based on surface mount phase leading bandpass unit cells using low temperature cofired ceramic(LTCC)","authors":"Po-Sheng Huang, Shuan-An Wei, Shan-Fon Hong, T. Lin, Pai-Yu Chen, Hsin-Chia Lu","doi":"10.23919/EUMC.2012.6459240","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459240","url":null,"abstract":"Surface mount unit cells for phase leading bandpass networks are developed for easy integration with microstrip lines on PCB for the phase shifter implementation. With the suitable design of layout and fabricated in low temperature cofired ceramic (LTCC), the bandpass network and its parasitic components are controlled to ensure the broadband operation. These unit cells of phase leading bandpass networks are mounted with phase lag microstrip lines on PCB for the design of broadband phase shifters. Unit cells can be cascaded in a single branch of power divider to create large phase shift or placed at different branch to give small phase shift while keeping sufficient return loss bandwidth. Four phase shfiters with phase shift of 22.5°, 45°, 90° and 135° are fabricated and measured using three different unit cells. Measured results of all four phase shifters show about 100% phase shift bandwidth, better than 10 dB return loss and less than 1.4 dB imbalance from 2.6 to 7.7 GHz.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130058663","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 : 2012-10-01DOI: 10.23919/EUMC.2012.6459385
G. P. Zouros, J. Roumeliotis
The cutoff wavenumbers of the elliptical dielectric waveguide are obtained through analytical expressions, when the eccentricity h of the elliptical core is specialized to small values. In this case, analytical, closed-form algebraic expressions, free of Mathieu functions, are obtained for the cutoff wavenumbers. These expressions are valid for every different value of the indices s and n, corresponding to every higher-order hybrid mode. Numerical results are given for various higher-order modes, as well as a comparison with the exact solution.
{"title":"Analytical calculation of cutoff wavenumbers of dielectric waveguides with elliptical cross section","authors":"G. P. Zouros, J. Roumeliotis","doi":"10.23919/EUMC.2012.6459385","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459385","url":null,"abstract":"The cutoff wavenumbers of the elliptical dielectric waveguide are obtained through analytical expressions, when the eccentricity h of the elliptical core is specialized to small values. In this case, analytical, closed-form algebraic expressions, free of Mathieu functions, are obtained for the cutoff wavenumbers. These expressions are valid for every different value of the indices s and n, corresponding to every higher-order hybrid mode. Numerical results are given for various higher-order modes, as well as a comparison with the exact solution.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130788152","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 : 2012-10-01DOI: 10.23919/EUMC.2012.6459434
C. Kakoyiannis, P. Constantinou
A printed circular inverted-F antenna (CIFA) is mirrored against a small, crescent-like ground plane (GNDP). The whole radiator is printed on a discoid substrate that conforms to the element and the ground plane. The edge of the PCB conforms to the circumscribing sphere. The CIFA-plus-GNDP combination is an electrically small element designed with only three parameters: two angles and a radius. It is resonant and matched at 2.5 GHz, where it achieved a 3.5% fractional impedance bandwidth. The antenna is highly efficient (91-95%) and approaches Thal's limit on minimum Q-factor within 27%.
{"title":"Electrically small, circular inverted-F antenna based on a robust, minimal design space","authors":"C. Kakoyiannis, P. Constantinou","doi":"10.23919/EUMC.2012.6459434","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459434","url":null,"abstract":"A printed circular inverted-F antenna (CIFA) is mirrored against a small, crescent-like ground plane (GNDP). The whole radiator is printed on a discoid substrate that conforms to the element and the ground plane. The edge of the PCB conforms to the circumscribing sphere. The CIFA-plus-GNDP combination is an electrically small element designed with only three parameters: two angles and a radius. It is resonant and matched at 2.5 GHz, where it achieved a 3.5% fractional impedance bandwidth. The antenna is highly efficient (91-95%) and approaches Thal's limit on minimum Q-factor within 27%.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132894300","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 : 2012-10-01DOI: 10.23919/EUMC.2012.6459421
K. Gomi, S. Hiura, M. Suzuki
A low-loss grounded coplanar waveguide (GCPW)-to-rectangular waveguide (WG) transition in a multilayer resin substrate for millimeter-wave applications is presented. The structure for the proposed transition is composed of a GCPW, a patch antenna and a quasi-dielectric waveguide (QDWG) in a multilayer resin substrate. The QDWG is formed by surrounding through holes, and the length of the QDWG is a quarter of the guide wavelength (λg). In this transition, a metallic WG is not used for a back short to simplify the structure. The dimensions and pattern layouts for the new GCPW-to-WG transition are designed with consideration of the estimated anisotropic permittivity of the resin substrate. Measurement results indicate a transition loss of 0.39 dB at a frequency of 77 GHz and a bandwidth of 5.6 GHz for a reflection coefficient below -20 dB, which corresponds to a fractional bandwidth of 7.3%. These results show the low transition loss of the planar-waveguide-to-WG transition which does not require an additional metallic WG for a back short. By applying the proposed GCPW-to-WG transition to a multilayer circuit board on which monolithic microwave integrated circuits (MMICs) are directly flip-chip-mounted, a high-performance, low-cost and compact transceiver module can be obtained.
{"title":"Low-loss GCPW-to-WG transition in multilayer resin substrate for millimeter-wave applications","authors":"K. Gomi, S. Hiura, M. Suzuki","doi":"10.23919/EUMC.2012.6459421","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459421","url":null,"abstract":"A low-loss grounded coplanar waveguide (GCPW)-to-rectangular waveguide (WG) transition in a multilayer resin substrate for millimeter-wave applications is presented. The structure for the proposed transition is composed of a GCPW, a patch antenna and a quasi-dielectric waveguide (QDWG) in a multilayer resin substrate. The QDWG is formed by surrounding through holes, and the length of the QDWG is a quarter of the guide wavelength (λg). In this transition, a metallic WG is not used for a back short to simplify the structure. The dimensions and pattern layouts for the new GCPW-to-WG transition are designed with consideration of the estimated anisotropic permittivity of the resin substrate. Measurement results indicate a transition loss of 0.39 dB at a frequency of 77 GHz and a bandwidth of 5.6 GHz for a reflection coefficient below -20 dB, which corresponds to a fractional bandwidth of 7.3%. These results show the low transition loss of the planar-waveguide-to-WG transition which does not require an additional metallic WG for a back short. By applying the proposed GCPW-to-WG transition to a multilayer circuit board on which monolithic microwave integrated circuits (MMICs) are directly flip-chip-mounted, a high-performance, low-cost and compact transceiver module can be obtained.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133010960","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 : 2012-10-01DOI: 10.23919/EUMC.2012.6459100
A. Tijhuis
In this paper, a two-stage approach is proposed for using computational electromagnetics the synthesis of antenna systems and other RF devices. engineering. First, stochastic optimization techniques are used in combination with approximate models. Second, line-search techniques are combined with full-wave modeling.
{"title":"Electromagnetic engineering a position paper","authors":"A. Tijhuis","doi":"10.23919/EUMC.2012.6459100","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459100","url":null,"abstract":"In this paper, a two-stage approach is proposed for using computational electromagnetics the synthesis of antenna systems and other RF devices. engineering. First, stochastic optimization techniques are used in combination with approximate models. Second, line-search techniques are combined with full-wave modeling.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133642506","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 : 2012-10-01DOI: 10.23919/EUMC.2012.6459372
T. Ueda, J. Fukuda, Y. Kado, T. Itoh
A new method of controlling phase nonreciprocity is proposed in composite right/left handed transmission lines with normally magnetized ferrite substrate. In the present approach, geometrical asymmetry is employed for the nonreciprocal phase control by changing electrical lengths of double shunt stubs inserted on both sides of the center microstrip line. To verify the basic concept, the nonreciprocal phase characteristics are investigated numerically and experimentally by changing the stub lengths for epsilon-negative high-pass structures keeping with the cut-off frequency fixed.
{"title":"Nonreciprocal phase-shift CRLH transmission lines using geometrical asymmetry with periodically inserted double shunt stubs","authors":"T. Ueda, J. Fukuda, Y. Kado, T. Itoh","doi":"10.23919/EUMC.2012.6459372","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459372","url":null,"abstract":"A new method of controlling phase nonreciprocity is proposed in composite right/left handed transmission lines with normally magnetized ferrite substrate. In the present approach, geometrical asymmetry is employed for the nonreciprocal phase control by changing electrical lengths of double shunt stubs inserted on both sides of the center microstrip line. To verify the basic concept, the nonreciprocal phase characteristics are investigated numerically and experimentally by changing the stub lengths for epsilon-negative high-pass structures keeping with the cut-off frequency fixed.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131318879","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 : 2012-10-01DOI: 10.23919/EUMC.2012.6459084
L. Boccia, A. Emanuele, E. Arnieri, A. Shamsafar, G. Amendola
In this work, preliminary results of a study on printed power combiners configurations for power-amplifier applications are presented. The proposed configuration is based on Substrate Integrated Waveguide (SIW) and multilayer PCB technologies. In particular, a printed horn combiner/divider was considered as a basic building block of a power combining amplifier. Simulated results of the passive combiners will be presented and discussed along with measured results.
{"title":"Printed power-combiner based on sectoral horns","authors":"L. Boccia, A. Emanuele, E. Arnieri, A. Shamsafar, G. Amendola","doi":"10.23919/EUMC.2012.6459084","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459084","url":null,"abstract":"In this work, preliminary results of a study on printed power combiners configurations for power-amplifier applications are presented. The proposed configuration is based on Substrate Integrated Waveguide (SIW) and multilayer PCB technologies. In particular, a printed horn combiner/divider was considered as a basic building block of a power combining amplifier. Simulated results of the passive combiners will be presented and discussed along with measured results.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124158612","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 : 2012-10-01DOI: 10.23919/EUMC.2012.6459189
D. Ribeiro, P. Cruz, N. Carvalho
Mixed-domain instruments are becoming extremely important in nowadays software defined radios industry. In that sense, instrumentation to characterize fast and accurately such components is necessary, in order to decrease the design complexity of software defined radios. In this paper a laboratory implementation of a mixed-domain instrument is presented as also a calibration procedure. The results obtained are afterwards compared with the available data and whenever possible with traditional approaches.
{"title":"Corrected mixed-domain measurements for software defined radios","authors":"D. Ribeiro, P. Cruz, N. Carvalho","doi":"10.23919/EUMC.2012.6459189","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459189","url":null,"abstract":"Mixed-domain instruments are becoming extremely important in nowadays software defined radios industry. In that sense, instrumentation to characterize fast and accurately such components is necessary, in order to decrease the design complexity of software defined radios. In this paper a laboratory implementation of a mixed-domain instrument is presented as also a calibration procedure. The results obtained are afterwards compared with the available data and whenever possible with traditional approaches.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114858978","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 : 2012-10-01DOI: 10.23919/EUMC.2012.6459305
Ho-Soo Park, I. Song, Jea-Shik Shin, Moon-Chul Lee, Sang Uk Son, Chul-Soo Kim, Duck-Hwan Kim, Jing Cui
To suppress spurious mode of the BAW (Bulk Acoustic Wave) resonator, advanced lateral structures are proposed. Three different techniques of apodization, air-edge reflector and border frame are integrated. Firstly, apodization is the method to design a proper shape of resonator which avoids parallel edges. By doing so, spurious mode is significantly improved at main resonances. Secondly, air-edge reflector is the method which creates lateral air interface to suppress the acoustic wave leakage. The Qa (Q-factor at anti-resonance frequency) and kt2 are improved from 420 to 640 and 6.0% to 6.7%, respectively. Thirdly, border frame is a specific thickened frame in which lateral acoustic wave cannot propagate. The Qr (Q-factor at resonance frequency) and Qa are increased from 850 to 1040 and 550 to 1670, respectively. After three techniques are integrated, the maximum value of Qr and Qa are achieved 1130 and 1920, respectively. Three practical techniques considerably improved the Q-factor and kt2 of BAW resonator which are essential parameters for low loss and wide band of RF filter configuration.
{"title":"Advanced lateral structures of BAW resonator for spurious mode suppression","authors":"Ho-Soo Park, I. Song, Jea-Shik Shin, Moon-Chul Lee, Sang Uk Son, Chul-Soo Kim, Duck-Hwan Kim, Jing Cui","doi":"10.23919/EUMC.2012.6459305","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459305","url":null,"abstract":"To suppress spurious mode of the BAW (Bulk Acoustic Wave) resonator, advanced lateral structures are proposed. Three different techniques of apodization, air-edge reflector and border frame are integrated. Firstly, apodization is the method to design a proper shape of resonator which avoids parallel edges. By doing so, spurious mode is significantly improved at main resonances. Secondly, air-edge reflector is the method which creates lateral air interface to suppress the acoustic wave leakage. The Qa (Q-factor at anti-resonance frequency) and kt2 are improved from 420 to 640 and 6.0% to 6.7%, respectively. Thirdly, border frame is a specific thickened frame in which lateral acoustic wave cannot propagate. The Qr (Q-factor at resonance frequency) and Qa are increased from 850 to 1040 and 550 to 1670, respectively. After three techniques are integrated, the maximum value of Qr and Qa are achieved 1130 and 1920, respectively. Three practical techniques considerably improved the Q-factor and kt2 of BAW resonator which are essential parameters for low loss and wide band of RF filter configuration.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116394382","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：