移动通信天线基础

bugbaggio

一
【文件名】:0698@52RD_antenna999.pdf
【格　式】:pdf
【大　小】:996K
【简　介】:1. Introduction
In the last few years a large technological jump has taken place in the field of mobile communications
due to the introduction of new mobile communication networks (GSM/PCN). The number of subscribers
worldwide has risen to over 150 Million. Fig. 1 shows an overview of the mobile communications services
and the relevant frequency ranges within Germany alone.
The requirements on the antennas needed for the ever expanding networks are becoming continually
higher:
– strictly defined radiation patterns for a most accurate network planning.
– growing concern for the level of intermodulation due to the radiation of many HF-carriers via
one antenna.
– dual polarization
– electrical down-tilting of the vertical diagram.
– unobtrusive design.
The following essay will give an insight into antenna theory in general, as well as the most important
types of antennas and the special methods used for GSM/PCN systems.



【目　录】:
1. Introduction P - 3
2. Theory P - 4
3. Definitions P - 5
3.1 Polarization P - 5
3.2 Radiation Pattern P - 5
3.3 Half-Power-Beam-Width P - 5
3.4 Gain P- 6
3.5 Impedance P - 6
3.6 VSWR/Return Loss P - 6
3.7 Mechanical features P - 6
4. Base Station Antennas P - 7
4.1 Omnidirectional Antennas P - 7
4.1.1 Groundplane and l/4-Skirt Antennas P - 7
4.1.2 Side-mounted Omnidirectional Antennas P - 7
4.1.3 Omnidirectional Gain Antennas P - 7
4.2 Directional Antennas P - 8
4.2.1 Gain Achieved via Horizontal Beaming P - 8
4.2.2 End-fire Array P - 8
4.2.3 Broadside Array P - 8
4.2.4 Antenna Systems P - 9
5. Particular Techniques used in GSM and DCS 1800 P - 10
5.1 Diversity P - 10
5.1.1 Space Diversity P - 10
5.1.1.1 Omni-Base Station P - 11
5.1.1.2 Sectored Base Station P - 11
5.1.2 Polarization Diversity P - 11
5.1.2.1 Horizontal and Vertical Polarization P - 11
5.1.2.2 Polarization +45°/-45° P - 12
5.2 Indoor Antennas P - 12
6. Car Antennas P - 13
6.1 l/4 Antenna on the Car Roof P - 13
6.2 Gain Antennas P - 14
6.3 Rear Mount Antennas P - 14
6.4 Screen Surface Direct Mounting Antennas P - 15
6.5 Clip-on Antennas P - 15
6.6 Electrically Shortened Antennas P - 15
6.7 Train Antennas P - 16
7. Antennas for Portables P - 17
7.1 l/4 Antennas P - 17
7.2 l/2 Antennas (Gainflex) P - 17
7.3 Electrically Shortened Antennas P - 18
7.4 Field Strength Measurements P - 18
共46页。

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john019

old

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