Chapter 3
| 1: | RF signals offer relatively short range as compared to light signals. True or false? |
| A1: | Answer: False. |
| 2: | What type of weather impacts RF signals the most? |
| A2: | Answer: Heavy rain. |
| 3: | Why does interference cause errors in wireless networks? |
| A3: | Answer: The interference causes the receiver to misunderstand the signal because two signals are present at the same time. |
| 4: | What are sources of RF interference? |
| A4: | Answer: General examples include cordless phones, microwave ovens, and Bluetooth devices. |
| 5: | Multipath affects higher data rates more than lower data rates for 2.4 GHz systems. True or false? |
| A5: | Answer: True. The receiver has difficulties with differentiating one bit from another when demodulating high data rate signals because the bits are close together. |
| 6: | What is meant by a diffused infrared light system? |
| A6: | Answer: A system that emits light in all directions that reflects off of the ceiling and walls. |
| 7: | Approximately up to what range do direct infrared systems operate? |
| A7: | Answer: 1 mile. |
| 8: | How does modulation make it possible to transmit information through the air? |
| A8: | Answer: Modulation superimposes an information signal onto a carrier signal that has a frequency suitable for propagating through the air. |
| 9: | What attributes of a signal does QAM change in order to represent information? |
| A9: | Answer: Amplitude and phase. |
| 10: | Spread spectrum generally requires user licenses. True or false? |
| A10: | Answer: False. |
