MITS5003 Wireless Networks & Communication - 2019SS Case Study Submission Due Date: 20/01/2020 before 5 pm Submission Guidelines: All submissions are to be submitted through turn-it-in. Drop-boxes...

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MITS5003 Wireless Networks & Communication - 2019SS Case Study Submission Due Date: 20/01/2020 before 5 pm Submission Guidelines: All submissions are to be submitted through turn-it-in. Drop-boxes linked to turn-it-in will be set up in the Unit of Study Moodle account. Assignments not submitted through these drop- boxes will not be considered. Submissions must be made by the due date and time. The turn-it-in similarity score will be used in determining the level if any of plagiarism. Turn-it-in will check conference web-sites, Journal articles, the Web and your own class member submissions for plagiarism. You can see your turn-it-in similarity score when you submit your assignment to the appropriate drop-box. If this is a concern you will have a chance to change your assignment and re-submit. However, re-submission is only allowed prior to the submission due date and time. After the due date and time have elapsed you cannot make re-submissions and you will have to live with the similarity score as there will be no chance for changing. Thus, plan early and submit early to take advantage of this feature. You can make multiple submissions, but please remember we only see the last submission, and the date and time you submitted will be taken from that submission. Your document should be a single word or pdf document containing your report. Designing a High speed Wireless Data Link Line of Sight Link Budget Analysis Several major factors that can impact the performance of a radio system are • Available/permitted output power, • Bandwidth, • Receiver sensitivity, • Antenna gains • Environmental conditions In this case study, the students will be required to calculate the link budget for a LOS Wireless link. Read through the following to understand some of the aspects and elements that need to be considered when calculating a Link Budget. Received Power If the estimated/calculated received power is sufficiently large (relative to receiver sensitivity), the link budget is sufficient for sending data. Received Power (dBm) = Transmitted Power (dBm) + Gains (dB) − Losses (dB) Gains(dB)=Transmit Antenna gain+ Receiver Antenna Gain Receiver sensitivity is the lowest power level at which the receiver can detect an RF signal and demodulate data. Link Margin/Fade Margin The amount by which the received power exceeds receiver sensitivity is called the link margin/fade margin. In wireless systems, multipath propagation results in multiple copies of a signal to arrive at different signal phases at the receiver. If these signals add up destructively, the resulting signal power can be lower by a factor of 100 or 1000 (20 or 30 dB). The signal level relative to the noise declines making signal detection at the receiver more difficult. It is therefore highly recommended to keep a link margin of 30 dB when designing a wireless system. Link Margin=Received Power-Receiver sensitivity Losses In a line-of-sight wireless system, losses are mainly due to free-space path loss (FSPL). Other losses are due to antenna cabling and connectors. Generally, 0.25dB loss per connector and 0.25dB loss for every 3-ft of antenna cable should be included in the link budget calculations. However, for the sake of simplicity, you can neglect these losses for your calculations. ????(??) = 10 ???10 ( 4??? ? ) 2 In dB’s the path loss when the distance (d is in km) and the frequency (f is in MHz) can be simplified as follows: ????(??) = 20???10(?) + 20???10(?) − 147.55 -------------------------------------------------------------------------------------------------------------------------------------- (a) Calculate the FSPL in dB for a distance of 5Km and 10 Km for two different frequencies 2.4GHz, 5.8GHz and construct a table as follows: FSPL(dB) Distance(Km) 2.4GHz 5.8GHz 5 10 (b) For the information given below, calculate the link budget analysis for the wireless system, which will involve calculating the following: • Received Power • Link Margin Distance: 10 km Frequency: 2.4 GHz Link Type: Point-to-Point, Line-of-Sight Tx power: +23dBm Antenna gain is 24dBi Assume negligible loss for cabling and connectors Receiver Sensitivity: -72dBm Assume that we are using the same antennas at the transmitter and the receiver side, the link budget calculations will be the same as the link budget in both directions is expected to be symmetrical. In cases where 2 types of antenna systems with different transmit power are used, we must perform two link budget analysis, one in each direction. (c) For the calculated Link Margin at 5Km what can you say about the availability/reliability of the link based on the following Table which shows the relationship between the available link margin and link availability as a percentage of time. Time Availability (Percentage) Link/Fade Margin 90 8 99 18 99.9 28 99.99 38 99.999 48