Wireless Communications and Networking -Free-Samples for Students

Questions: 1. Different antenna, such as yagi, horn, and celluar antennas, etc. has different merits. Research these technologies in details and pay specific attention to how they are used as well their strengths and weakness. Provide an opinion regarding which antenna types will become the dominant players in the future of medium- and long-distance wireless links 2.Compare and contrast the multiplexing techniques CDMA and FDMA in the area of Wireless Networking? Answers: 1.There are different types of antennas such as yagi, horn as well as cellular antennas. Yagi antenna is highly directional radio aerial made of various short rods. These are mounted across insulating support as well as transmitting as well as receiving narrow band of the frequencies. The antenna includes multiple parallel components in a line, generally half-wave dipoles developed by metal rods. The key element of Yagi antenna theory has three phases of currents, which are flowing in additional components of the antenna. On the other hand, a horn antenna or microwave horn is known as antenna, which includes flaring metal waveguide that is shaped like a horn for directing the radio waves in beam. In addition, horns are utilized as antennas at UHF as well as microwave frequencies above the range of 300 MHz (Paschen, 2016). Cellular antennas are used in conjunction with the powered signal booster such as inline amplifier or the repeater that are connected directly to the cell phone or the devices with cell phone adapter cable or the coax adapter. The cellular signal reception has negatively affect through several factors that include several obstructions. In yagi antenna there is high gain that provides relatively good range. On the other hand, yagi has most of the gaining for physical size compared to the other antennas such as log periodics. The design of yagi antenna can filter out all signal noise that is usually coming from the opposite directions. It makes yagi preferable antenna for high demand application like telecommunications. Smart cellular antenna provides increased security as the signals are not radiated in all direction. However, bandwidth or frequency range is limited. On the other hand, in order to get beam radiation antennas made with long run. It is helpful for making directional diagram narrower than the aperture width (Lias et al. 2013). Cellular antennas emphasizes on communicating devices that has range of operation increased. It allows the area service to increase. In addition, there are security facilities for using cellular antenna. However, this type of antenna is complicated, expensive and larger sized. Analyzing the advantages and disadvantages of three type of antennas, it can be considered that cellular antenna will become dominant in future of wireless links for having a number of benefits such as increased bandwidth reduced interference, security as well as increased range. 2.Frequency is a technology through which total bandwidth available to the system divided into frequencies. The particular division is achieved between the non-overlapping frequencies assigned to each of the communicating pair. In addition, FDMA is generally utilized for analog transmission. However, the technology is not able carrying digital information. In this perspective, it is not considered that efficient method is required for digital transmission. On th other hand, if the frequencies need handling the customers, it is important to understand the technology better (Betz, 2013). In FDMA, the entire band of frequencies is usually divided into several RF channels or carriers. Each of the carriers are allocated to distinctive users. For an instance, entire frequency band having 25 Mhz is usually divided into 124 RF carriers that has bandwidth of 200 KHz. In the application of satellite, entire transponder band with 500 HHz is divided into 24 channels. There are generally two main types of FDMA scheme utilized in satellite network such as single channel per carrier as well as multiple channels per carrier. On the other hand, Code Division Multiple Access has entire bandwidth shared among several users through unique codes. For an example, CDMA IS-95 standard of entire bandwidth 1.225 MHz can be shared through several codes. Unlike FDMA, CDMA isolates calls by code. These are labeled with a specific code. The relevant framework gets a call and distributes type of code to specific discussion. The information is a part into some little parts. These are labeled with the exceptional code given to which they are a piece of (Song et al. 2016). The framework can toward the end reassembles to the provided discussion from coded bits as well as conveys it. CDMA spread the spectrum through orthogonal codes. Every terminal is active at the same point getting uninterrupted. In terms of call capacity, there is no absolute limitation on the capacity of channel. However, it is considered as interface that is limited system. Moreover, it is flexible and has less frequency for which planning is needed. On the other hand, transmission scheme is continuous. Signal separation of CDMA has code plus special receivers. However, in CDMA, there is complicated and more complicated power controls for the senders. References Betz, J. W. (2013). Signal structures for satellite-based navigation: past, present, and future.Inside GNSS,8, 34-42. Lias, K. B., Buniyamin, N., Narihan, M. Z. B. A. (2013, December). An overview of cancer thermal therapy technology based on different types of antenna exposure. InElectrical, Electronics and System Engineering (ICEESE), 2013 International Conference on(pp. 96-101). IEEE. Paschen, D. (2016, June). Paul MayesSeries antenna arrays. InAntennas and Propagation (APSURSI), 2016 IEEE International Symposium on(pp. 1073-1074). IEEE. Song, Q., Nuaymi, L., Lagrange, X. (2016, April). Evaluation of multiple access strategies with power control error and variable packet length in M2M. InWireless Communications and Networking Conference Workshops (WCNCW), 2016 IEEE(pp. 379-384). IEEE.