1. Echo-suppression devices, developed in the late 1950s, were first employed to manage echo generated primarily in satellite circuits.

2. The two distinct areas of echo cancellation are acoustic and hybrid echo cancellation.

3. Hybrid echo results from converting four-wire trunk circuits to two-wire local cabling using a device called a "hybrid."

4. Today's digital cellular network technologies, namely TDMA, CDMA, and GSM/PCS, require significantly less processing power to transmit signal paths through channels.

5. When a mobile user calls a fixed network customer, unacceptable call quality can result at the fixed end of the link. In addition, certain digital handsets add an offset to the transmit signal, causing degradation of digital cellular's speech compres

6. The explosive growth in the wireless telecommunications industry in this decade has been a result of which of the following?

7. Which of the following is the term for the amount of time that the canceller has to hold the model of the echo in order to recognize and cancel it?

8. Although not a factor in itself on digital cellular networks, which of the following becomes a problem in PSTN–originated calls?

9. Digital processing delays are encountered as signals are processed through various network routes, such as which of the following?

10. Which factor is expected to bring digital wireless telephony much closer to matching wireline quality?