Question

1. What is “LOS"? a. LOS is 2. What is WSN? a. Wireless Sensor Networks are 3. Visual LOS implies RF LOS a. True or False 4. A 1-km 2.4 GHz link has two antennas that are 2m above ground. Do we have LOS? a. Yeyor No 5. In free spate RF power loss ~1/R^2 but when the transmitter and receiver is close to the ground, the loss can be -1/R14 a. True or False 6. What is RSSI? How is it used in WSNs? a. RSSI is 7. What are ISM bands? a. ISM bands are 8. ISM bands are unregulated a. True or False 9. Explain with a simple sketch and paragraph how multipath propagation can diminish or enhance radio propagation a. UGH 10. What is BER? a. BER is 11. A manufacturer claims its radio can make reliable reception if the received power is - 105dBm. How many mW is this? Are you impressed? a. There is 12. Explain TDMA a. TDMA is 13. Explain FDMA a. FDMA is 14. Explain what spread spectrum communication is (To Grandma) a. Spread Spectrum Communication is 15. What is S/N and SNR? a. S/N is 16. What are common units of SNR? a. Common Units are 17. Everything else being equal, RF path loss are higher at 2.5 GHZ than at 900 MHz a. True or False 18. Estimate the path loss in dB at 900 MHz in an indoor environment. There are two floors and six walls between transmitter and receiver. a. Estimate 19. The antennas of a 2.4 GHz RF link are Im above ground and are 100m apart. Is the path loss -1/R^2 or -1/R^4? Is the communication LOS? a.