Reduced size antennas for mobiles :Full project report

This thesis aims at designing reduced size of the antennas elements which when used with an RF transceiver adapts with the radiation pattern and ensures better communication between master and slave mobile computers. In order to obtain a maximum efficiency, the project concentrate only on the antenna elements which is suitable to work in the bandwidth range of 2.45Ghz.the choice of the band is based on the fact that it is an ISM band which does not require permission for performing any experimental tests, another reason is that the antenna can be integrated to work with any standard communication devices that operate in this band such as IEEE802.11b standard and Bluetooth. Another advantage is that the Bluetooth modules and its associated w softwares are available in market by many manufactures at affordable prices so it becomes easy for any final year student to pursue this thesis.
From the last ten years we are being witnessing the rapid development of wireless communication which was possible mainly due to the advancements in the field of digital communication. This led to the transformation of the technology into many fields from military field. Since the digital communication had many advantages like resistance with noise and interference etc and better security with encoding techniques, makes it special unlike its analogue counterpart. These features assisted the rapid growth of the 2nd and 3rd generations of cellular phone systems.

The tremendous success of the cellular voice communication has led to the interest of using the radio communication technologies into other fields like wireless communication. Initially wireless computing was a process of inter linking computer and other devices sans wire and making it to perform all the operations like accessing, storing etc that was originally done by the devices using the wire, for example accessing the internet using a wireless acesspoint in places like hospitals universities etc, for the purpose of providing communication between the computers different part of electromagnetic spectrum can be used for transmission over the air, example Infra red radiations and light frequencies can be used but for using them there must not be any obstacles in between the line of site but this is only possible in indoors within less than 1 meter. laser communication also encounters the same problem even though it can be established over several kilometres, for achieving a non line of site communication we can make use of lower range electromagnetic spectrum  namely radio frequencies. An application of a particular radio frequency band depends on specifications of the communication range and the bandwidth of the information-carrying signal. Lower range of radio frequencies is able to cover larger distances. However, this is at the expense of a narrower bandwidth for the signal carrying the message. Which was a disadvantage another shortcoming was the size of the antennas which was required for the launch of the radio signal from RF circuit in to the free space.

For a traditional antenna to work efficiently its size must be half of the free space wavelength so for 1Ghz the antenna must be 15 cms but apparently for microwaves and millimetre waves utilizing  more than or above 1Ghz can offer a reduction in the size of the material radiating. The same frequencies can also offer substantial bandwidth for the information-carrying signal. For example, if it is assumed that a radio transducer operates over a 10% bandwidth, a 100MHz BW for a 1GHz carrier frequency system is theoretically obtainable.

The design and usage of the wireless computers needs a specific frequency band available for it. Everybody knows that the Radio Frequency spectrum is not a free commodity and it’s being governed by specific bodies to avoid its interference by irresponsible users. The other reason is that particular frequency bands can be allocated to specific services. Due to the importance of some offered services, a given frequency band, treated as commodity, may be worth of billions of dollars when auctioned by a government to competing bidders (companies).

Download this final project report on this link: http://goo.gl/aT9l8