PayLoad Octet Calculations (MB-OFDM)

Menu Path: MeasSetup > MB-OFDM Demod Properties > Time tab

PayLoad Octets specify the number of payload data bits (in units of Octets) included for measurement analysis. The PayLoad Octets determine the measurement packet length, the length of the Packet Time trace and Packet Spectrum trace data. A PayLoad Octets value of 0 (default) represents a packet consisting of the 12 Header symbol-times and 0 Payload symbol-times.

PayLoad Octets is a function of Result Length and Data Rate. Changing the Result Length setting will cause the number of PayLoad Octets to be changed and changing PayLoad Octets will cause the Result Length to be changed.

PayLoad Octet Calculation

The ceiling function forumula is used to calculate the PayLoad Octets:

where: Payload Symbols = Result Length -12, and

InfoBits value is provided in the Data Rates table.

MB-OFDM Orthogonal Frequency Division Multiplexing: OFDM employs multiple overlapping radio frequency carriers, each operating at a carefully chosen frequency that is Orthogonal to the others, to produce a transmission scheme that supports higher bit rates due to parallel channel operation. OFDM is an alternative tranmission scheme to DSSS and FHSS. Data Rate Parameters
Data Rate (Mb/sec)	Modulation Type	Coding Rate	FDS	TDS	Coded Bits*	Info Bits*	Preamble
53.3	QPSK Quadrature phase shift keying	1/3	Yes	Yes	300	100	Standard
80.0	QPSK	1/2	Yes	Yes	300	150	Standard
106.7	QPSK	1/3	No	Yes	600	200	Standard
160.0	QPSK	1/2	No	Yes	600	300	Standard
200.0	QPSK	5/8	No	Yes	600	375	Standard
320.0	DCM	1/2	No	No	1200	600	Standard/ Burst
400.0	DCM	5/8	No	No	1200	750	Standard/ Burst
480.0	DCM	3/4	No	No	1200	900	Standard/ Burst
* Per (6) OFDM Symbols