Abstract
Pulse amplitude modulation (PAM) is used extensively in telecommunications as an intermediate step of other techniques such as phase shift keying (PSK), quadrature amplitude modulation (QAM) and pulse code modulation (PCM) 1. PAM however is an amplitude modulated (AM) form of a pulse carrier2, and hence has all the advantages and disadvantages of the purely analog AM, a major disadvantage being noise. PAM can be time-division multiplexed (TDM), as can pulse code modulation (PCM) which is a digital signal. TDM is one of the multiplexing techniques used in telephony (the other is space-division multiplexing). PAM is used as a first step in converting voice signal to PCM in the public switched telephone network (PSTN), and is also used to produce high-level modulation schemes for data modems and digital radio. High-level modulation is done in the output circuit of the radio frequency (RF) power amplifier stage, and is more efficient than low-level modulation. PCM is used for long-distance telecommunications, making PAM an important pulse modulation technique in communications systems.
Original language | English (US) |
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Pages (from-to) | 6685-6690 |
Number of pages | 6 |
Journal | ASEE Annual Conference Proceedings |
State | Published - 2001 |
Event | 2001 ASEE Annual Conference and Exposition: Peppers, Papers, Pueblos and Professors - Albuquerque, NM, United States Duration: Jun 24 2001 → Jun 27 2001 |
All Science Journal Classification (ASJC) codes
- General Engineering