INTRODUCTION
Mobile communications, wireless interconnects, wireless local area networks (WLANs), and cellular phone technologies compose one of the most rapidly growing industrial markets today. The advancement in the direction of wireless communication leads to a great demand of development of compact antenna to support multiple applications that can be easily integrated within the small space that is available inside the device. In the case of, portable antenna technology has grown along with mobile and cellular technologies. Proper antenna for a device is the most important factor. This will improve transmission and reception of signals, reduce power consumption, long lasting and improve marketability of the device.
Antennas used for early portable wireless handheld devices where the so-called whip antennas. The whip quarter-wavelength antennas were more popular because of its simple and convenient design [1]. It has an Omni-directional pattern in the plane of the earth when held upright and a gain satisfying the device’s specifications. A new antenna designs are implemented on radios with a lower profile than the whip antenna and without significantly reducing performance. These antennas include the quarter-wavelength helical shape and the stubby helical antenna, which is the shortest available antenna.
In recent years, the demand for compact handheld communication devices has grown. So devices smaller than the palm size have appeared in the market. The size of antenna is a major factor that limits device miniaturization. In the last few years, new designs based on the compact Planar Inverted-F shaped Antenna (PIFA) and Micro strip Antennas (MSA) have been popular for handheld wireless devices because these antennas have ...
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1.5 HIGH FREQUENCY STRUCTURE SIMULATOR (HFSS)
HFSS is the industry-standard simulation tool for 3D full-wave electromagnetic field. it provides E-field and H-fields, S-parameters, currents and near and far radiated field. HFSS is an engineering design tool that is automated solution process where users are only required to specify material properties, geometry and the desired output. here HFSS will automatically generate an efficient ,accurate and appropriate mesh to solve the problem using the proven finite element method.
The core of the program HFSS is based on the finite element method (FEM) (its practical application often known as finite element analysis (FEA)) where it is a numerical technique for finding approximate solutions to partial differential equations (PDE) and their systems, as well as (less often) integral equations.
Esquire Radio & Electronics, the plaintiff, has filed a law suit against Montgomery Ward, seeking damages for a breach of contract.
The word oscilloscope is a word that combines from Latin and Greek language. The first part “oscillare” derives from the Latin words meaning to swing backwards and forwards. The second part comes from Classical Greek “skopein” means to observe, aim at, examine, from which developed the Latin ending “scopium”, which has been used to form names for instruments that enable the eye or ear to make observation.
This first handheld cell phone weighed 2.4 pounds and was 9 x 5 x 1.75 inches in size. For reference, the iPhone 6 is 5.44 x 2.64 x 0.27 inches and weighs just 129 grams (0.28 pounds). The first handheld cell phone also had only 20 minutes of battery life when talking. Once the phone battery was drained, it took approximately 10 hours to charge back up fully. As phones change, society changes along with it because people rely on their phones for everything. As phones develop people develop with them. And People have evolved to have everything they need right in their pockets.
INTRODUCTION Would people be willing to pay $12.50/month for commercial free radio beamed right to their car or home. Well two companies and many big investors are betting about $3 billion dollars that people are willing to do just that. In 1997, the Federal Communication Commission (FCC) granted a portion of the S-band spectrum for satellite radio and two companies purchased use of these bands and started the only two companies competing in the satellite radio business today, namely Sirius and XM. Analysts like William Kidd of CE Unterberg Towpin, predict satellite radio will generate about $10 billion a year in revenues by 2007 (McClean, 2001).
Here we design single-antenna based system which checks the traffic probe regarding the communication between different users in a connected area under coverage. To increase the coverage area and traffic collection, we can increase the antenna gain and amplifiers with noise reduction techniques. There are some procedures, experiments and also theorems in implementing the right way of tracking the forensic devices. As in this experiment the limit of detection is around 1km of radius and the accuracy of forensic localization has a error limited to 10 meters which is a serious threat to location privacy.
Cell phones use radio frequencies to transmit signals. Radio Frequencies (RF) are a form of electrical waves similar to those used in radios, microwaves, radars or satellite stations. They are emitted from a transmitter, and received using an antenna. This telephony technology is restricted geographically to small zones called “Cells”. Every cell has a base station capable of sending and receiving radio waves. When a call is started a signal leaves the handheld unit headed to the closest base station. This station answers by allocating a specific channel to the unit. When this “channel” is established, modulated radio frequency signals are both received and transmitted. The head of the user is in the near field of use because the distance from the antenna to the head is a few centimeters. (Blettner & Berg 2000) If the antenna is inside the body of the phone, the exposure to Radio Frequencies is greater. The antenna might be requesting a stronger signal to contest with the interference of the battery or the actual shell of the phone’s body.
Walking around in school to walking around at the shopping centre with your mobile phone may seem fashionable and trendy, but did you know that it might be causing you to get a cancer and brain damage threw lost of memory? . Many mobile phone holders do not realize it and it should be something everyone should be aware of. It may seem a bit unusually how a Mobile phone can cause a child or an adult to get cancer, but it is true. New evidence is growing fast about health risks from mobile phones – electromagnetic radiation. These devices can be used to make telephone calls from almost any country in the world to another.
Print. The. Gordon A. Gow, and Richard K. Smith. Mobile and wireless communications: an introduction, McGraw-Hill International, 2006. Print.
An oscilloscope is an electronic test instrument that is used to observe an electronic signal, typically voltage, as a function of time. In other words, it is a voltage versus time plotter. Oscilloscopes come in two basic types, analogue or digital, and support various features and functions useful for measuring and testing electronic circuits. An oscilloscope is a key piece of test equipment for any electronics designer.
Cell Phones: A portable phone that uses wireless technology to send and receive phone signals. This technolog...
The world has gone through a lot of changed as time passes by. With advancements in the technological field people are can communicate with ones from around the world without having to even lift a finger. To make things more efficient and more cost saving industries have made technology wireless. Wireless technology gives people the chance to get up from their stationary computer, or cord phone and able to freely move without restrictions. The IT, or Information Technology has become a standard and very critical part of today’s society. Wireless technology came from the basic just cellular usage to sensors in the medical field. Wires are now a thing of the past in today’s world with forever revitalizing technology.
When the generated fields pass through magnetic materials which themselves contribute internal magnetic fields, ambiguities can arise about what part of the field comes from the external currents and what comes from the material itself. It is common to define another magnetic field quantity, usually called the "magnetic field strength" designated by H. It can be defined by the relationship, H = B0/μ0 = B/μ0 – M, and has the value of unambiguously designating the driving magnetic influence from external currents in a material, independent of the material's magnetic response. The relationship for B can be written in the equivalent form, B = μ0(H + M), H and M will have the same units, amperes/meter. To further distinguish B from H, B is sometimes called the magnetic flux density or the magnetic
Cell phones are devices that emit radio frequency electromagnetic waves commonly referred to as RF-EMW (Brossner, Davoudi, and Kuber 19). Signals are transmitted through these waves from cellular devices to large antennas and centralized base stations (19). Studies show that excessive cell usage of four or more hours daily can affect male fertility greatly (19). The reproductive system of men is super sensitive and compartmentalized (19). Exposure to electromagnetic waves and currents may have some effect on count of sperm and motility (19). This is due to sperms electrically active cellular nature (19).
During the increase in popularity of radio, Arthur Edwin Kennelly said (1926) "through radio I look forward to a United States of the World. Radio is standardizing the peoples of the Earth, English will become the universal language because it is predominantly the language of the ether. The most important aspect of radio is its sociological influence." Kennelly was foreseeing the potential power and impact that radio would soon come to have. By the late twenties, we would see radio become quite the sensation in the household, and this sensation would continue to prosper even through the Great Depression with aid of soap operas and popular programs such as the Lone Ranger. Radio would see a decrease in popularity during the rise of the television. Eventually, radio would find itself a niche in the media market, allowing it to continue to prosper. This would be due to the help of Frequency Modulation radio broadcasting and localization. Radio stations were now able to offer more local content than radio, touching on local news, weather, and advertisements for local businesses all at a higher sound quality. That joined with a symbiotic relationship with the recording industry and the start of formatted radio programs, the two industries were set to last for almost another fifty years (Adams, n.d.).
Cell phones represent a type of technology that has been around for more than over fifty years; it has only been recently that many people began to use cell phones as a major part of their everyday life. In the past cell phones were for business people to conduct their business, but in today’s society every one owns a cell phone. Cell phones are interesting, useful and also play a major role in our life’s bringing people closer and keeping in touch with one another. Most people do not know and understand the physics of a cell phone. Cell phones are also known as cellular phone, hand phone, and commonly known as a mobile phone. A cell phone is an electric device that can make and receive calls, over and automatic repeat request (radio link petrol -RLP) used over wireless air interdace.it us a portable telephone that uses and receive phone signals.it also divides that earth into small regional called cells.in the resent estimates there are over 190 million people using mobile phone. One of the primary health concerns is the impact of cell phone radiation, by radio waves by which it operates.