Code Division Multiple Access - Essay Example

Chapter 4 Exercises Table of Contents Exercise 3 Exercise 2 5 Exercise 3 7 Exercise 4 8 10 Works Cited 11 Exercise The history of computers s back to the early 1940s when ENIAC was invented and introduced. However it was mainly developed for the scientists. With the passage of time other forms such as mainframe computers, mark I computers etc. were invented. After that the development process continued and mankind entered the age of information technology. The importance of computers was like never before. Starting from schools, colleges to business houses and scientific laboratories, computers were of prime importance. As the growth continued the concept of internet also came and it revolutionized the world. Internet connected the world and thus made the communication process more effective. In the early days a base phone and a dial up modem was used to connect the internet, but after that cable connection was invented and it increased the speed of internet. Soon after that, wireless connections were also introduced and it offered a speed of 20 Mbps. Another advantage of wireless connection is the wider area of coverage, which is not possible in cable connections. With the passage of time, the hardware section also got tremendously modified. There were enhanced and modern versions of computers were invented. The new forms came forward in the form of laptops, notebooks, tablets, Smartphone etc. Similarly other peripherals also got invented, such as printers, webcams etc. However, all the aforementioned computing devices have different uses and different functions. The software market is also the same, there have been large developments. Software such as SPSS and Office suite has changed the business world. Also there were introduction of open source software, which offered free software to the customers. Advancement of technology has also allowed the manufacturers to come up with large number of variants for a product. A user therefore gets the opportunity to choose from various technical specifications. One of the most important digital inventions came in the form of digital cameras. In simple words it revolutionized the world of photography. It not only got technologically advanced but succeeded in making ‘unlimited photography’. With the help of memory cards, users can now click as much pictures as they want. Now whether it is a digital camera or a computing device, users chooses to buy it depending upon the purpose of the user. Once the purpose gets decided the next step is to compare the technical specifications and price of the items. Most of the users consider the present trends of market in deciding the product as well as product specifications. For example, if a user likes to purchase a gadget for the primary rationale of playing games, he/she has the choice of a desktop, notebook, laptop and even a tablet. Hence in this scenarios market trends are useful. Table I – Market Trends of computing devices Tablet 2008 2009 2010 2011 2012 Notebook 45 % 44 % 44 % 44 % 43 % Net-book 9 % 18 % 18 % 17 % 17 % Tablet N/A N/A 6 % 13 % 18 % Desktop 45 % 38 % 32 % 27 % 23 % The above data clearly portrays that tablet computers have already started to gain large market shares, while the demand of desktop computers is falling down. Nevertheless personal preferences and requirements also act as a decisive factor. Exercise 2 The factors that are to be considered while buying a laptop is as followed:- 1. Screen Size: - One of the most important factors is the size of the screen. The screen sizes are generally 14.1 inch, 15.1 inch and 10.1 inch. Hence according to according to the requirements, a user can choose the screen size. 2. Processor and Memory: - The processor and memory is an important factor as it determines the speed at which the laptop will function. 3. Connectivity: - Nowadays connectivity is extremely important. It includes Wi-Fi, Bluetooth and data cable. Therefore users can choose the desired connectivity accordingly. 4. Power Backup: - It is imperative to consider the power backup of a laptop while buying it. Since it is a handy item, users may use it anywhere and thus power backup is important. 5. Graphics & Video Output: - A large group of users consider multimedia as an important section of the laptop. Hence high resolution graphics and video output is also important. Table I – Comparison of Laptops Model/Laptop Apple Mac-Book Air Samsung Series 7 Gamer Dell Inspiron 14z Price $1,139.00 to $1,199.00 $1,749.90 to $2,018.88 $899.99 Display 13.3 inch LED backlight 17.3 inch LED backlight 14 inch Backup up to 7 hour(s) up to 4.5 hours up to 6 hours Review It has an elegant design and has some dynamic features. However the essential Ethernet port is absent. It has an implausible screen, blazing graphics and processor and several ports. A new slim looks with core i5 processor at an affordable price. However the concern lies with the battery life and budget. Cnet Rating **** **** **** (Source: “Apple MacBook Pro with Retina Display”) The three laptops chosen are Apple Mac-Book Air, Samsung Series 7 Gamer and Dell Inspiron 14z. The reason behind choosing them is the buzz that they have been able to generate in the recent past and the market share of these brands is also high. Exercise 3 Presently I am using Apple IPhone 4S, which has been designed on a GSM platform. It is also a smart phone with several pre-installed applications. I have already completed the speed test at speedtest.net and I have recoded the following outcomes. Ping: 117ms Download Speed: 4.19 Mbps Upload Speed: 1.24 Mbps Now based on the findings from the cnet.com the battery type and its life is presented below. Battery Technology: Lithium ion. Talk Time in WCDMA platform - up to 480 min. Talk time in GSM platform - up to 840 min. Total Standby Time - Up to 200 hours. Internet browsing in WCDMA profile - up to 6 hours. Internet browsing through Wi-Fi - up to 9 hours. Video playback time - up to 10 hour(s). Audio Playback time - up to 40 hour(s). Now the radiation rate or the SAR rating is given below:- Mobile/Model Number SAR Rating Radiation Rate Apple IPhone 4S 1.6 W/kg 1.11 (“Cell phone radiation levels”). (Source: “Cell phone radiation levels”). Exercise 4 CDMA stands for Code Division Multiple Access, while GSM stands for Global System for Mobile Communications are two mobile network technologies (Mullett 229-230). CDMA is developed by Qualcomm in the United States and GSM has been developed the European Telecommunications Standards Institute. Nevertheless they are not only limited to general differences only, but there are large numbers of technical differences as well. The technical differences are as follows:- Network: CDMA has only one physical channel along with a special code for each of the devices in the coverage network. Now using this special code, the device signal gets multiplexed and the signal is sent via the same channel. In case of GSM every unit has a subsequent network coverage that serves the mobiles in that particular region. SIM Cards: In CDMA based mobiles, the SIM remains connected with the network. Hence there is no need to insert an external SIM. On the other GSM networks does not comes with a pre loaded SIM and the users have to insert SIM from external sources. Hence GSM users enjoy the authority to alter their SIM cards at any moment of time. Furthermore The CDMA platform is faster and more secure than that of a GSM platform. Network Coverage: In general GSM networks have wider network coverage. It is mainly because of the tie ups with other GSM networks. Presently I am using IPhone 4S, which has been designed on a GSM platform. The primary rationale behind opting for the GSM network is its wider network coverage and higher compatibilities in comparison with a mobile designed on a CDMA platform. Figure 1- CDMA vs. GSM (Source: “Difference between GSM and CDMA”) Works Cited “Apple MacBook Pro with Retina Display.” Cnet. CBS Interactive, 2012. Web. 16 Oct. 2012. “Cell phone radiation levels.” Cnet. CBS Interactive, 2012. Web. 15 Oct. 2012. “Difference between GSM and CDMA.” Discusstech. n.p., 2011. Web. 15 Oct. 2012. Mullett, Gary J. Wireless Telecommunications Systems and Networks. Connecticut: Cengage Learning, 2006. Print. Read More