EEL 4599 Wireless & Mobile Networks Homework 2 Worksheet Page 1 of 2 Due Tuesday, February 13, 2024 , 11:59pm Homework Assignments are Individual Assignments. Studying with others is okay to get the concepts. Any copied or duplicated work will be considered cheating. HW 2 has 2 parts: (1) the worksheet (30 points) and (2) the quiz (70 points). This is the HW2 worksheet. Answer the questions below. Answers must be in your own handwriting (on tablet or on paper). Points will be deducted for typed answers. Scan and save your HW2 worksheet in a file called < lastnameHW2.pdf >. Submit your file to the HW2 Worksheet Assignment link in Canvas. On the same day the worksheet is due, you will take the online HW2 quiz. The quiz is open book, open web, open worksheet, but you will not be given the solutions to the Worksheet before the Quiz. 1. Consider a base station tower with two service providers. The first provider operates unity gain antennas at a frequency of 875 MHz. The second providerβs unity gain antennas operate at twice the frequency, that is, at 1750 MHz. Calculate the path loss in dB observed at 1 km in each case assuming free-space propagation. 2. In a mobile communication network, the minimum required signal-to-noise ratio is 12dB . The background noise at the frequency of operation is β115ππ΅π . If the transmit power is 23π , transmitter antenna gain is 3ππ΅ i, the receiver antenna gain is 2ππ΅π , the frequency of operation is 900MHz, determine the maximum in-building signal penetration loss that is acceptable for a base station with a coverage of 5km . Use the free-space path loss model, i.e., alpha=2. 3. Suppose the mean of the local average received powers at a certain distance is -30dBm, that the standard deviation of shadow fading is 9 dB, and that the observed received power is above the threshold 95% of the time. What is the threshold power? In other words, what is the value of gamma in Prob{Pr(d)) > gamma}? Hint: This property will be needed Q(x) = 1 β Q(-x). 4. Consider the figure below, found in the Week 4 lecture notes and Pahlavan Section 11.4.1, and answer questions a, b and c below. Figure 1. GSM TDMA a. As discussed in lecture, GSM uses a multi frame transmission. (Figure 1 above.) Demonstrate through calculations that the transmission rate of GSM is 270.833 kbps, based on the frame structure shown in the figure. bits The g uard time , G, between frames is equivalent to 8.25bits sent at the GSM data rate. EEL 4599 Wireless & Mobile Networks Homework 2 Worksheet Page 2 of 2 Due Tuesday, February 13, 2024 , 11:59pm b. The shown multiframes each use 26 frames total β 24 for traffic and 2 for association control signaling. Demonstrate through calculations that the effective transmission rate is 22.8Kbps for voice traffic in GSM using the burst frame. c. For each slot in the 26-slot traffic multiframe, the slow association control channel uses 114 bits. Calculate the transmission rate for the slow association control channel in bps. 5. Refer to Week 4 lecture notes and Pahlavan Sections 4.2.1, 4.2.2, and 11.4.1 Figure 2. Frequency bands in GSM a. Figure 2 above shows the GSM frequency allocation process. Suppose the system uses two-way GSM communications. For 50 MHz of bandwidth, what is the total number of traffic channels? b. For 1MHz of bandwidth, what is the total number of GSM channels? 6. Given the standards shown (and referring to the lecture notes βWeek 04 - Multiplexing.pdfβ, slides 31-36),... System LTE Region Global Access method OFDM/TDMA/FDD Modulation Scheme 64 QAM Frequency band (MHz) 5 Carrier spacing (KHz) 180 Frame duration (ms) 10 Bearer channels/carrier 10 7. Consider a CDMA system with 3 users, A, B, C, with k=6 A: cA=<-1,-1,-1,+1,+1,+1> B: cB =<+1,+1,-1,-1,+1,+1> C: cC =<+1,-1,+1,-1,+1,-1> a. If A transmits the data 1 0 1, what is the transmitted pattern? b. What is the correlation between the transmitted pattern and Aβs chip pattern? c. What is the correlation between the transmitted pattern and Bβs chip pattern? d. What is the correlation between the transmitted pattern and Cβs chip pattern? 8. For a system with a bandwidth of 3MHz, a data rate of 19,200bps and a minimum acceptable bit-energy to noise density ratio of 10dB, determine the maximum number of users that can be supported this single-cell CDMA system. Problem 9 will be moved to HW 3. 9. Consider Zigbee (Xbee) as described in the lecture notes and/or textbook Section 9.3 and answer the following questions. a. What is the IEEE standard number? b. What is the purpose of a Zigbee network? c. List the operating frequencies for Zigbee and the maximum data rates for each. EEL 4599 Wireless & Mobile Networks Homework 2 Worksheet Page 3 of 2 Due Tuesday, February 13, 2024 , 11:59pm d. What is the multiplexing/channelization protocol for Zigbee? e. What is the medium access control (MAC) protocol for Zigbee? f. What type of modulation is used in Zigbee? g. How many RF channels are available in Zigbee? h. How many devices can be supported in a one-hop Zigbee network.