Advantages And Disadvantages Of An Antena

The different forms of antenna technology refer to single or multiple inputs and outputs. These are related to the radio link. In this way the input is the transmitter as it transmits into the link or signal path, and the output is the receiver. It is at the output of the wireless link.

Here first we design a simple rectangular shaped microstrip patch antenna with dimension 14 X 14 X 1.60 mm^3 shown in Fig.1. In this antenna the dimension of patch is 10 X 13 mm^2. We are using microstrip line feed to this rectangular patch with length 4mm and width 1.6mm. By simulating this simple patch antenna we were getting only two frequency bands as shown in Fig2.

On old radios the antenna was detrimental to the radio’s operation. Today, the antenna is not necessary. AM radio does not have as good of quality as FM but it can travel farther distances. FM signals can be interfered by things such as mountains or other barrier

Electromagnetic waves are continually used to upgrade and advance our technology, being implicated for its use in microwave ovens, radio waves for telecommunications and x-rays in medicine.

First of all the radio has a lot of history and an impact on society. On January 1, 1863 the very first radio was built by Nikola Tesla. Nikola Tesla made the radio to “listen to”, or “listen with.” The radio was connected to a radio wave. For instance the radio was

The military has many uses for electromagnetic waves. They use it in the kitchen all the way to the battlefields. They use radio waves for seeing the damage that space dust could make. They use microwave radiation for cooking. They use Infrared waves for looking for enemies. They also use visible light to send streams of data. Two more waves are X-Rays and gamma rays. X-Rays are used for looking through other objects. Gamma rays are used for explosives.

Window embedded wire antennas have been introduced at FM frequencies for low-power or receive-only applications. The power transmitted by the army radios at VHF and UHF frequencies can exceed tens of watts. At these power levels, it is of crucial importance to isolate the interior of the vehicle from the antenna radiation. In addition, this isolation eliminates the affects of the cabin interior and passengers on the antenna input impedance and radiation pattern. Hence a transparent ground plane will be needed behind the radiating element to reduce the radiation inside the vehicle and at the same time increase the directivity of the antenna. A wire-mesh or a more sophisticated band-selective ground plane can be used as the reflecting element. A meshed patch antenna on a mesh ground plane can provide the required isolation with the cabin interior. However because of the sub-wavelength dimensions of the armored windows at VHF and UHF frequencies a patch antenna, if feasible, cannot provide the one octave bandwidth required by the army radios. In this paper a monopole bow-tie antenna backed by a cavity (armored window) is proposed. Because of the limited thickness of the window glass, the radiation element and the transparent ground plane need to be placed very close to each other. Therefore the gain and/or the

The equation for radiation resistance is given in (1). As can be seen, the greater the radiation resistance, the more energy is radiated or received by the antenna. When the radiation resistance of the antenna matches the resistance of the transmitter or receiver, the system is optimized. Antennas also have ohmic or loss resistance which decreases efficiency. It can be shown that an efficient antenna must be comparable to a wavelength in size.

The fig.3 and 4 above is a simulated result showing the red is return loss (S11) and blue is insertion loss (S21) obtained for model. Figure 4 shows the reflection and transmission factor measured for the range 1 GHz to 4GHz. This result gives that the bandpass characteristics are valid for a wide range of EM spectrum for communication. In order to get detailed characteristics in the neighborhood of 2.45 GHz, Figure 4 gives more information needed to the measurement results. With the 3 dB boundary, we get about 260 MHz bandwidth, and insertion loss of -4.3 dB, with parametric dimension as given in Table.1.

The antennas on this tower are attached to a metal pole and structure themselves with an Antenna Array as visible in the screenshot. This structure can usually carry from 3 to 18 antennas, depending on the number of wireless carriers and volume of transmission. Also, by using the Antenna Array, the antenna can increase the overall gain and cancel out interference from a particular set of directions. Another benefit of the Antenna array is that it maximizes the Signal to Interference Plus Noise Ratio The tower is located at 2716 46th Street Tampa, FL. It is composed of many omnidirectional antennas that point on different views and angles. The current tower coordinates point to Latitude 27.9677 and Longitude -82.4077. As I mentioned before, it is required by the Federal Communications Commission that any antenna which height more than 200ft above ground level will be registered to avoid interferences. I searched for this information in the Antenna Structure Registration section of the Federal Communication Commission and below there is the

So the transmitter can increase the output of the antennas in the direction of computers farther away or where there are more computers to allow for better coverage or throughput and decrease the output of the antennas in directions where there are obstacles.

another cell phone. Once one of the RF channel is modulated one of the radio signals are then

The classic RF structure has a transmitter and a receiver. The transmitter creates electrical signals that are called a carrier signal. The carrier signal frequency is determined by the wave length. The carrier signal is modulated to carry voice by adding a contrast signal to the wave form. The receiver gets the pair of sidebands and transforms them into speech or other sounds. RF in a wireless environment can have dead spots due to line of sight issues.

Once the transformer sends out the radio signal, it is sent to the crystal oscillator which is another important part. The oscillator makes an electromagnetic frequency by vibrating a piece of crystal. Once it is modified by the oscillator, the signal is complete and ready to be broadcasted.

The comparison graph of the simulated result in return loss (dB) versus frequency (GHz) between the conventional rectangular microstrip patch antenna and proposed compact antenna is shown in of fig. 3.7 and the comparison graph of the measured and simulated result of the compact antenna is shown in fig. 3.9.Antenna is fabricated and experimentally tested to valid the design of the antenna