Hi am Neethu. i would like to get details on printed antenna ppt.i need your help

In telecommunication, there are several types of microstrip antennas (also known as printed antennas) the most common of which is the microstrip patch antenna or patch antenna.

Microstrip Patch Antenna
Microstrip patch antennas are among the most popular antennas, used in various application areas. Model building for this type of antennas can be done in two ways: in WIPL-D general-purpose 3D modeler and in the tool specialized for printed structures, AW Modeler. A simple microstrip patch antenna is simulated here. The simulated results are verified with measurements performed by WIPL-D staff.
The antenna is printed on RT Duroid 5880 substrate of height 1.5748 mm and of complex permittivity 2.2(1-j 0.0004). The model is made on a finite substrate and over finite ground plane (Fig. 1). The copper conductor is taken with finite conductivity of σ = 19 MS/m, to account for surface roughness. The antenna is fed by a probe that is extended to a coaxial line. A part of the coaxial line is included in WIPL-D model to simulate effects of realistic coaxial feed .
Calculated data are presented on the performance of printed antenna elements on substrates which may be electrically thick, as would be the case for printed antennas at millimeter wave frequencies. Printed dipoles and microstrip patch antennas on polytetrafluoroethylene (PTFE), quartz, and gallium arsenide substrates are considered. Data are given for resonant length, resonant resistance, bandwidth, loss due to surface waves, loss due to dielectric heating, and mutual coupling. Also presented is an optimization procedure for maximizing or minimizing power launched into surface waves from a multielement printed antenna array. The data are calculated by a moment method solution.

Printed Antennas

This type of antenna is popular for applications requiring:

Planar antennas.
Efficient radiators.
Arrays for low or medium directivity.
2 GHz upwards.
Lightweight, simple construction and cost effectiveness.
arrayantenna


The communications group has facilities for complete prototyping of printed antennas of almost any geometry. Popular designs include ISM band arrays (medium gain antennas at 2.45 GHz and also 5.85 GHz). A 12 element 2.45 GHz uniform array is shown below, which offers 12 dBi of gain.

Overall dimensions are 300 x 200 mm. The substrate used is a low-loss microwave laminate of thickness 0.79 mm and dielectric constant 3.2 The radiation patterns are fully characterised.

Other printed antennas are in current use on Communications Group projects, such as low gain patches for propagation studies at 2.5 and 5.8 GHz, and medium gain arrays for communications links using Radar Transponders at 9.4 GHz. (Link to X-band antenna )


Antenna Radiation Patterns


pat2


Plot of H-plane radiation pattern of printed array antenna showing relative gain as a function of angle-measured (Red), theory (Blue)