me refractory metals and one dimensional superconductors

... Ultra-Wideband (UWB) Communications Channel – Theory and Measurements Ultra-Wideband (UWB) Communications Channel – Theory and Measurements 29 random variables within one snapshot (bin) of measurement ... Channel – Theory and Measurements References Environment Measur Time Res.∗ Tech (ns) Measurement Grid Grid Size Spacing (cm) Frequency-Bandwidth Absolute (GHz) Relative (17)-(23) Office and Laboratory ... Communications Channel – Theory and Measurements Ultra-Wideband (UWB) Communications Channel – Theory and Measurements 39 13 PDP, i.e the mean excess delay τm and the root mean square delay spread τRMS...

Ngày tải lên: 29/06/2014, 13:20

... tìm hiểu thiết kế Boadband Planar Monopole Antennas Đồng thời sử dụng phần mềm Ansoft HFSS để thiết kế mô Đồ án gồm chương : Chương 1: Lý thuyết chung anten Chương 2: Boadband Planar Monopole Antennas ... đơn giản để bao phủ dải tần số 225-400 MHz 2-6 GHz TÀI LIỆU THAM KHẢO [1] Girish Kumarand, K.P.Ray, 2003 Broadband microstrip antennas ArtechHouse London [2] Lưu Văn Hoan, 2008 Thiết kế anten vi ... thực tế nghiên cứu phân tích tỉ mỉ Với loại anten khác, trở kháng vào xác định thực nghiệm BROADBAND PLANAR MONOPOLE ANTENNAS: 2.1 Giới thiệu: Ta biết BW MSA tăng lên với gia tăng độ dày chất giảm...

Ngày tải lên: 21/08/2015, 16:38

... Broadband Wireless Communication 243 Haoshuo Chen, Rujian Lin and Jiajun Ye 14 Measurement and modeling of rain intensity and attenuation for the design and evaluation of microwave and millimeter-wave ... Radiometers 169 Jian Dong and Qingxia Li 10 Antenna Measurement 193 Dominique Picard 11 The interference between ground plane and receiving antenna and its effect on the radiated EMI measurement ... measurement The antenna brings into measurement additional errors, which increase measurement uncertainty These errors and their effect on the entire uncertainty of the measurement are investigated in the...

Ngày tải lên: 21/06/2014, 11:20

... officers in distress, and injured skiers or climbers and children lost in the mall or amusement park And with UWB tracking mechanisms, we can not only know item locations and their movement but also ... antennas include 24 Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment the equiangular geometries of planar and conical spiral structures and the logarithmically periodic ... achievable and maintained over much wider bandwidths by adding more dipole antenna elements The performance of a LPDA is a function of number of elements as well as element length, spacing and diameter...

Ngày tải lên: 21/06/2014, 11:20

... the antennas Fig 21 Geometries and dimensions of test printed monopole antennas [39] 76 Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment Fig 22 Measured S11 for test ... time is saved considerably since only the patch needs to be discretized and not the feeding network The advantage of memory space and simulation time becomes clear in table Patch Antennas and ... three -dimensional structures with bulky volume In the late 1950s and early 1960s, a family of antennas with more than 10:1 64 Microwave and Millimeter Wave Technologies: Modern UWB antennas and...

Ngày tải lên: 21/06/2014, 11:20

... source, x-band amplifier1, Wide/narrow switch and step attenuator and 0.5W amp are measured by the power meter and the results are given in table Noise source x-band amp1 Wide/narrow switch and step ... Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment 3.4 The intermediate receiver section and circuit design The front end board output signal is entered to the intermediate ... designed and implemented on a Rogers-5880 microstrip board that was explained completely in section 3-4  Delay Element 92 Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment...

Ngày tải lên: 21/06/2014, 11:20

... and equipment To evaluate the performance of aperture synthesis radiometers at millimeter wave band, a one- dimensional prototype of aperture synthesis radiometer working at millimeter wave band, ... input impedance measurements are performed The first measurement is done with the antenna in free space and the second measurement with the antenna inside a metallic hemisphere, and the input resistance ... 1996] One method is a generalization of one- dimensional Leech’s construction described in section 3.1(b), that is, by multiplying one- dimensional basis of the form in (11), one can obtain the twodimensional...

Ngày tải lên: 21/06/2014, 11:20

... for radio disturbance and immunity measuring apparatus and methods – Part 2-3: Methods of measurement of disturbances and immunity –Radiated disturbance measurements IEC Standard, December 2006, ... interference (EMI) measurement is two-valued, i.e „pass / fail“, the measurement is the most complex and the most time-consuming measurement of all of electromagnetic compatibility (EMC) measurements The ... numerical calculation – simulation based on “method of moments” 216 Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment Radiated EMI measurement 2.1 Principle of measurement...

Ngày tải lên: 21/06/2014, 11:20

... transmission speed In Millimeter-wave (mm-wave) band (30-GHz ~300GHz), about 270-GHz bandwidth can be utilized, which is ten times the bandwidth in Centimeter-wave band (3-GHz~30-GHz) Moreover, ... spacing and steering angle ones The highest sensitivity, as in the SLL1 analysis, is shown for the steering angle 238 Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment ... of mobile and wireline subscribers 244 Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment By increasing operating frequencies of wireless system, a broader bandwidth...

Ngày tải lên: 21/06/2014, 11:20

... of DSD Measurement and modeling of rain intensity and attenuation for the design and evaluation of microwave and millimeter-wave communication systems 273 proposed by Marshall and Palmer (1948) ... climate, the measuring instrument, the number of samples, and the year of measurement A more in-depth study is required to identify the real causes of the disagreements Measurement and modeling ... 20 o C ) and (b) Real and Imaginary parts of relative permittivity r Measurement and modeling of rain intensity and attenuation for the design and evaluation of microwave and millimeter-wave...

Ngày tải lên: 21/06/2014, 11:20

... Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment Finally, the Z-parameters which are transformed from S-parameters are compared with measured results and simulation by Momentum ... The on-chip meander CPW resonator is designed, fabricated, and measured using TSMC 0.18 m CMOS technology This process has 1-poly and 6-metal layers and the thickness of the top metal is 3.1 ... UWB antennas and equipment Design Techniques for Microwave and Millimeter Wave CMOS Broadband Amplifiers 345 18 x Design Techniques for Microwave and Millimeter Wave CMOS Broadband Amplifiers...

Ngày tải lên: 21/06/2014, 11:20

... performed using multi-port computer models based on S-parameter measurements in an ADS co-simulation platform These results show relative speed and range measurements MULTI-PORT TECHNOLOGY AND ... V and W bands are presented and analyzed In addition, a Ka band demodulator and a W-band radar sensor prototype are presented Present and future works are focused on UWB multi-port receivers and ... Theory and Techniques Symposium, pp 1553-1556, 1994 388 Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment Li, J., Bosisio, R.G & Wu, K (1995) Computer and Measurement...

Ngày tải lên: 21/06/2014, 11:20

... obtained by simulations and measurements 432 Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment (b) (c) Fig 15 Comparisons of simulation- and measurement-results about ... characterization (d) Time-domain measurements: In order to allow operation in the specified frequency band and to meet the conditions stated in section 2.2, time-domain measurements were made for a Gaussian ... needed prior to implementation and measurements (b) Implementation of the proposed prototype: To check for the validity of the aforementioned theoretical predictions on NGD and PC, a proof-of-principle...

Ngày tải lên: 21/06/2014, 11:20

... analyze requirements to high performance magnetron based radar and discuss some methods to meet them 4.2 Transmitter 4.2.1 General consideration As mentioned above the modern requirements to the ... usually some implementation of a frequency discriminator In this case it is very difficult to meet both above requirements at the same time Actually in order to achieve a high precision measurement ... sign of the frequency offset can be measured, and the result of the measurements is 486 Microwave and Millimeter Wave Technologies: Modern UWB antennas and equipment practically independent on the...

Ngày tải lên: 21/06/2014, 11:20

... Standing Wave Ratio TH Time Hopping UWB Ultra – Wide Band Trang SVTH : NGUYỄN HOÀI ANH GVHD : Th.S NGUYỄN DƯƠNG THẾ NHÂN PHẦN I : XÂY DỰNG CƠ SỞ LÝ THUYẾT CHƯƠNG : TỔNG QUAN VỀ ULTRA - WIDE BAND ... Trong truyền dẫn không liên tục, xung liên tiếp gửi frame thời gian Các frame (Tf) xác định mã dịch thời gian giả ngẫu nhiên (Pseudo Random Time – Hopping Code) Do độ rộng xung nhỏ, thời gian lặp ... Th.S NGUYỄN DƯƠNG THẾ NHÂN CÁC TỪ VIẾT TẮT BPF Band-Pass Filter BW BandWidth CDMA Code Division Multiple Access CEPT European Conference of Postal and Telecommunications DSP Digital Signal Processing...

Ngày tải lên: 22/06/2014, 14:47

... frequency components or first on the time components, that is, the first and the second combining stages can be interchanged Assuming (a) rich scattering environment (where, up to 7-fold time diversity ... carrier in l the lth time slot (due to fading) and ξn is the phase offset in the nth carrier and lth time slot (due to fading) (hereafter, this phase is assumed to be tracked and removed) The fades ... carrier component is removed from the incoming signal, and the signal is split into N branches (one per carrier component) On the nth branch, the nth carrier is returned to baseband and separated...

Ngày tải lên: 23/06/2014, 01:20

... Broadband Wireless Communication 243 Haoshuo Chen, Rujian Lin and Jiajun Ye 14 Measurement and modeling of rain intensity and attenuation for the design and evaluation of microwave and millimeter-wave ... Radiometers 169 Jian Dong and Qingxia Li 10 Antenna Measurement 193 Dominique Picard 11 The interference between ground plane and receiving antenna and its effect on the radiated EMI measurement ... measurement The antenna brings into measurement additional errors, which increase measurement uncertainty These errors and their effect on the entire uncertainty of the measurement are investigated in the...

Ngày tải lên: 27/06/2014, 01:21

... TRANSACTIONS ON ANTENNAS AND PROPAGATION, VOL 57, NO 7, JULY 2009 Fig Measured maximum gain on the E- and H-planes Fig 3-dB beamwidth of the radiation patterns on the H- and E-planes Fig Measured radiation ... Y L Chow, and K F Lee, “Broadband microstrip patch antenna,” IEE Electron Lett., vol 34, no 15, pp 1442–1443, Jul 1998 [14] Z N Chen and M Y W Chia, Broadband Planar Antennas: Design and Applications ... components, (a) the length of the radiator Ltop , and (b) the height H1 of the vertical strip The resonant frequencies are estimated by f 108  2( 2+ top fl ; fh ; L n n nH1 Fig Measured and...

Ngày tải lên: 10/07/2014, 01:20

... and Discussion A prototype with the mentioned dimensions was built and measured The prototype was built in 0.5mm brass, and a sheet of eccosorb [7] was employed as absorber Figure shows the measured ... desired frequency band Measured and simulated gain in broadside direction is plotted in figure Measurement '4 SirTulation Figure Input impedance from 3GHz to 6GHz Simulation and Measurernent Ga.in ... width W and slot length L: W 16 - = - = L (2) 0.0625 The antenna was evaluated using the software packages IE3D and XFDTD IE3D is a commercial method of moments code [5] XFDTD is a commercial...

Ngày tải lên: 10/07/2014, 01:20

... thank C Meagher for helping in the measurements, and the anonymous reviewer’s comments that helped in improving the presentation of this paper REFERENCES [1] R Garg, P Bhartia, I Bahl, and A Ittipiboon, ... co-polarization gain components vary from 5.80 dBi at 2.80 GHz (start of the bandwidth) to almost dBi as frequency exceeds GHz, and then it become 4.10 dBi at 12.60 GHz (end of the bandwidth) Similarly, ... the start and end of the bandwidth they not overlap The parameters provide all the important system parameters in terms of the gain, impedance matching, polarization matching, path loss and phase...

Ngày tải lên: 10/07/2014, 01:20