Signal constellation diagram
CONTENTS Introduction Basic Concepts of Digital to analog modulation PSK QAM Introduction What is Signal Constellation diagram ? . Representation of signal modulated by a digital modulation. . They also help you visually understand how a particular modulation mechanism works. . Bit rate . Baud rate Digital to Analog Modulation Is the process of changing one of the characteristics of an analog signal based on information in a digital signal(0s and 1s). Example data from computer to another across a public access phone line. Amplitude , frequency and phase. Types of digital/analog modulation Phase Shift keying(PSK) Phase of the carrier is varied to represent binary 1 or 0. Phase of 0 degrees to represent binary 0. Phase to 180 degrees to send binary 1. Conceptual view of PSK PSK Constellation 4PSK- Conceptual view 4-PSK Constellation diagram 8 PSK When we have eight possible phases ,we can send three bits at a time. 8-PSK is three times faster than 2-PSK Three bit represents by each phase is called a tribit. [...]...8-PSK Constellation diagram Quadrature Amplitude Modulation PSK is limited by the ability of the equipment This factors limits its potential bit rate Combine ASK and PSK Then we have maximum contrast between each bit QAM Constellations 4- QAM 8-QAM Time domain for an 8QAM 16- QAM Constellation Bit and Baud comparison Why are constellation maps or diagrams useful? They help... help you design a transmission system that is less prone to errors and can possibly recover from transmission problems without relying on higher level protocols The analysis of a transmission system's constellation map allows the development of error detection and error correction schemes that can detect transmission problems Thanks Indian Elango . Concepts of Digital to analog modulation PSK QAM Introduction What is Signal Constellation diagram ? . Representation of signal modulated by a digital modulation. . They also help you visually. contrast between each bit QAM Constellations 4- QAM 8-QAM Time domain for an 8- QAM 16- QAM Constellation Bit and Baud comparison Why are constellation maps or diagrams useful? They help you. 0. Phase to 180 degrees to send binary 1. Conceptual view of PSK PSK Constellation 4PSK- Conceptual view 4-PSK Constellation diagram 8 PSK When we have eight possible phases ,we can send three