AD9361 Reference Manual
UG-570
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INTRODUCTION
TERMINOLOGY
AGC
Automatic gain control where an algorithm in the
AD9361
controls the receive path gain.
BBP
Baseband processor (or digital baseband).
BB
Baseband. Baseband received signals are those that have already
been downconverted from RF. Baseband transmit signals are
those that have not yet been upconverted to RF.
BB DC Cal
Baseband DC calibration. An on-chip calibration that reduces
the DC power in the received data by adding digital correction
words to the data between the Half-Band 1 filter and the receive
FIR filter. See the Initialization and Calibration section for more
information.
BBP
Baseband processor (or, digital baseband).
Cal
Calibration.
DC
Literally direct current. In this document, DC refers to
undesired received power in the center of the complex received
baseband spectrum.
ENSM
Enable state machine. This on-chip state machine moves the
AD9361
through its states and it also controls other functions
within the
AD9361
. See the Enable State Machine Guide section
for more information.
FDD
Frequency division duplex in which transmit and receive signals
can be present at the same time but use different frequencies
LMT
LNA, mixer, TIA. LMT refers to the LMT gain table as well as
an analog peak detector that monitors the signal level at the
input of the analog LPF. See the Gain Control section for more
information.
LO
Local oscillator, which refers to the desired RF carrier frequency
for the receiver and the transmitter.
LPF
Low-pass filter, which refers to the third-order analog low-pass
filter preceding the receive ADC and following the transmit
DAC.
LUT
Look up table, several calibration and functions depend on
either reading or storing look up tables for future use.
MGC
Manual gain control where the BBP controls some or all of the
gain control parameters in the
AD9361
.
PLL
Phase locked loop. The
AD9361
uses PLLs to generate the
various clock rates within the chip as well as the Tx and Rx LO
frequencies.
RF
Radio frequency.
RF DC Cal
Radio frequency DC calibration is an on-chip calibration that
reduces DC power in the received data by applying a compen-
sating voltage between the LNA and the mixer. See the
Initialization and Calibration section for more information.
TDD
Time division duplex in which transmit and receive signals can
be present on the same frequency but at different times.
VCO
A voltage controlled oscillator (VCO) is a circuit in which the
output frequency of the oscillator is controlled by an input
voltage level. These VCOs are part of the PLLs on the
AD9361
.
The
AD9361
must calibrate the VCOs before the frequency they
produce is accurate and stable.
REGISTER AND BIT SYNTAX
When a register with absolute bit locations is described in this
user guide, the format is always in hex for the register and
[Dx:Dy] for the bits. This format is best described by an
example such as 0x016[D0], which equates to Register 0x016
(hex), and only the lowest bit of this register. Thus, the register
and the bit locations are specifically delineated.
When describing the value of just a few bits, the following
format is used: x’byyy.
where
x equals the number of bits described.
b indicates binary.
yyy represents three digital bits with values of 0 or 1.
As an example, if two bits equal 2’b01, then the LSB = 1 and the
next higher bit = 0.
Rev. A