In the following essay, each blank has four choices.Choose the best answer and write down on the answer sheet.
Spread spectrum simply means that data is sent in small pieces over a number of the{{U}} (10) {{/U}}frequencies available for use at any time in the specified range.Devices using{{U}} (11) {{/U}}spread spectrumDSSS) communicate by{{U}} (12) {{/U}}each byte of data into several parts and sending them concurrently on different{{U}} (13) {{/U}}.DSSS uses a lot of the available{{U}} (14) {{/U}}, about 22 megahertz(MHz).