Linear Ramps Using Extrapolation - MOGlabs ARF021 Manual

9.6 Linear ramps using extrapolation

9.6 Linear ramps using extrapolation
Note: This section describes the low-level implementation of parameter extrapolation.
It is strongly recommended to use the high-level helper functionality provided by the
TABLE,RAMP
command, which makes use of the extrapolate feature in
provides a simpler user interface.
TABLE,ENTRY
(3)
Warning:
Bounds checking is not performed in extrapolation mode; it is up to the
user to ensure that parameters do not go out of bounds. In particular, the power
is not obeyed, and amplitude must not go negative. It is strongly recommended to
check the output on an oscilloscope through an
device that could be damaged by maximum output power.
One of the powerful features provided in advanced table mode is
the ability to specify linear ramps in parallel mode, which reduces
the number of instructions necessary to produce smooth piecewise-
linear ramps. The
the as required. This means that a 1000-point ramp can be
DDS
implemented as a single table instruction instead of requiring 1000
different individual instructions.
The extrapolation feature is activated by specifying the
a table entry, using the syntax shown below.
TABLE,ENTRY,ch,num,param,delta,duration,REPn,flags
Sets the associated table entry to
param
the parameter
times as specified by
delta
The argument should be specified in hexadecimal when ex-
trapolating power/amplitude, as in this example. Hexadecimal val-
ues can be obtained from the output of the
end-point. Subtract the two and divide by the number of steps to
. Do not specify delta in dBm or W. Conversely,
delta
obtain the
TABLE,RAMP
the function does accept values in real-world units.
FPGA performs the extrapolation and updates
EXTRAPOLATE
on each execution. The instruction is repeated
REPn
.
RF attenuator before connecting to a
TPA mode and
REPn
flag in
delta
, adding
POW
command for each
LIMIT
81
to