Agilent Technologies ESG Guía de usuario Pagina 144

  • Descarga
  • Añadir a mis manuales
  • Imprimir
  • Pagina
    / 502
  • Tabla de contenidos
  • SOLUCIÓN DE PROBLEMAS
  • MARCADORES
  • Valorado. / 5. Basado en revisión del cliente
Vista de pagina 143
128 Chapter 3
Basic Digital Operation
Differential Encoding
Differential Encoding
Differential encoding is a digital-encoding technique whereby a binary value is denoted by a
signal change rather than a particular signal state. Using differential encoding, binary data in
any user-defined I/Q or FSK modulation can be encoded during the modulation process via
symbol table offsets defined in the Differential State Map.
For example, consider the signal generator’s default 4QAM I/Q modulation. With a
user-defined modulation based on the default 4QAM template, the I/Q Values table editor
contains data that represent four symbols (00, 01, 10, and 11) mapped into the I/Q plane using
two distinct values, 1.000000 and -1.000000. These four symbols can be differentially encoded
during the modulation process by assigning symbol table offset values associated with each
data value. The following illustration shows the 4QAM modulation in the I/Q Values table
editor.
NOTE The number of bits per symbol can be expressed using the following formula.
Because the equation is a ceiling function, if the value of x contains a fraction, x
is rounded up to the next whole number.
Where x = bits per symbol, and y = the number of differential states.
Vista de pagina 143
1 2 ... 139 140 141 142 143 144 145 146 147 148 149 ... 501 502

Comentarios a estos manuales

Sin comentarios