Title Simulation of CNT Antennas with SONNET®Problems and Limitations  Abstract This thesis is a part of bigger project, in which CNTs are to be investigated theoretically and experimentally. Accurate models would be developed on the basis of analysis with numerical electromagnetic solvers (e.g.  SONNET®).  These investigations would further be used in design and realizations of these antennas at Institute for Nanoelectronics at  Technische Universität München.  Impedance and radiation characteristics of the antennas will be measured and the measurements will be compared with the results of the numerical modeling. Salient features of SONNET® are studied by analyzing the results generated by simulations of Bow-Tie antenna and patch antenna, especially its limitations. Several models with different metal types in SONNET®  are looked into to see whether SONNET®  can deal with CNT networks which have conductive as well as dielectric properties. The cases when the metal sheet is very thin and thick enough are investigated to see how  SONNET®  works.  CNT antennas are modeled at last, but due to the problems and limitations of SONNET®, the results are not consistent with those measured in experiment. Further work needs to be done both in SONNET® and CNT antennas to know more.7483
 Keywords    CNT   SONNET®   Bow-Tie Antenna    Patch Antenna
Table of Contents
1     Motivation & Introduction  .  1
2     Carbon Nano-Tubes  .  2
2.1  Introduction to Carbon Nano-Tubes    2
2.1.1  Conductivity of CNT Networks  .  4
2.1.2  Permittivity of CNT Networks  .  5
2.2  CNT Application    5
3     Salient Features of SONNET®    6
3.1  Metal Types .  6
3.2  Dielectric Bricks    7
3.3  Ports  .  7
3.4  Box Resonances  .  7
3.5  De-embedding    7
4     Antenna Properties  .  9
4.1  Radiation Efficiency   9
4.2  Quality Factor    10
4.3  Bandwidth    11
4.4  Antenna Gain  .  12
4.5  Conclusion about the Parameters  .  12
5     Simulation with SONNET®    13
5.1  Bow-Tie Antenna  .  13
5.1.1     Bow-Tie Antenna with Different Metals  .  13
5.1.2  Bow-Tie Antenna with Different Angles  .  16
5.1.3  Bow-Tie Antenna with Different Lengths  .  18
5.2  Anomalies in Simulations and Limitations of SONNET®    19
5.2.1  Simulations with Low Conductivity    19
5.3  Limitation in Value of Surface Impedance    21
5.4  Investigations with Penetration Depth  .  23
5.4.1  Investigation of Skin Effect in very Thin Metal    23
5.4.2  Investigation of Skin Effect in Thick Metal  .  28
5.4.3  Investigation of Current Ratio in the Normal Metal Type  .  31
5.4.4  Investigation of Thick Metal Type  .  32
5.5  Other Kinds of Bow-Tie Antennas    36
5.5.1  Triangle Frame Bow-Tie    37
5.5.2  Loop Frame Bow-Tie  .  38
5.5.3  Thin Frame Bow-Tie    39
5.5.4  Thinest Frame Bow-Tie  .  40
5.5.5  Conclusion of Different Kinds of Bow-Tie Antennas .  41
5.6  Patch Antenna    42
5.6.1  Numerical Solution Techniques in SONNET®  .  42 Simulation of CNT Antennas with SONNET®Problems and Limitations :http://www.751com.cn/yingyu/lunwen_5467.html