GPS Antennas for Portables（13页）

neuqjiake

【文件名】:08926@52RD_GPS   Antennas  for  Portables.pdf
【格　式】:pdf
【大　小】:619K
【简　介】:Low cost, high performance Global Positioning System (GPS) antennas are in demand
for portable devices. The effects of partial dielectric loading and physical volume (height
and diameter) are very important factors in antenna design. Parameter tradeoffs have a
direct bearing on antenna pattern and therefore the overall usability of the system. This
presentation covers several aspects of small Quadrifilar Helical Antennas (QHA) relative
to portable GPS applications.
【目　录】:1 Introduction and Background ................................................................................................3
1.1 Customer Base Wants Small Antennas ........................................................................3
1.2 QHA Factors for Good GPS Operation .........................................................................3
2 QHA Characteristics..............................................................................................................3
2.1 General.........................................................................................................................3
2.2 Axial Height and Filar Length ........................................................................................3
2.3 Diameter.......................................................................................................................4
2.4 Pitch Angle ....................................................................................................................4
2.5 Driving Point Impedance ...............................................................................................4
2.6 Dielectric Loading..........................................................................................................4
3 Case Studies for Small GPS Quadrifilar Helical Antennas ...................................................4
3.1 Case Study 1. QHA Diameter of 13 mm and Pitch Angle of 60 Degrees.....................4
3.2 Case Study 2. QHA Diameter of 15 and Pitch Angle of 30 Degrees............................5
3.3 Case Study 3. Dielectric Loaded QHA Diameter of 12 mm and Pitch Angle of 30
Degrees........................................................................................................................5
4 Measured Results for 60 Degree QHA .................................................................................9
4.1 Measured Gain vs. Frequency for Diameter = 12 mm and Pitch Angle = 60 Degrees .9
4.2 Measured Efficiency for Diameter = 12 mm and Pitch Angle = 60 Degrees .................9
4.3 Measured Radiation Pattern for Diameter = 13 mm and Pitch Angle = 60 Degrees...10
5 Measured Results for 30 Degree QHA for Diameter = 12 mm and Pitch Angle = 30
Degrees.............................................................................................................................11
5.1 Measured Gain vs. Frequency for Diameter = 12 mm and Pitch Angle = 30 Degrees11
5.2 Measured Efficiency for Diameter = 12 mm and Pitch Angle = 30 Degrees ...............11
5.3 Measured Radiation Pattern for Diameter = 12 mm and Pitch Angle = 30 Degrees...12
6 Summary Discussion ..........................................................................................................13

neuqjiake

[em05][em02][em01]
自己顶顶。。。。。。。。

pengxx

先买了，以后再看，先谢了！

liuhero_008

[em01][em01]

franky_kin

thank you

lishichao211

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