Frequency Hopping With Rx/Orx Gain Control; Special Frequency Hopping Operations - Analog Devices ADRV9005 Reference Manual

Reference Manual ADRV9001
FREQUENCY HOPPING
Figure 131. Diversity Timing Example, Rx1/Rx2

FREQUENCY HOPPING WITH RX/ORX GAIN CONTROL

In FH operation, configure the receiver gain control as either manual gain control or automatic gain control (AGC).
Configure the AGC as in the non-FH mode and set it to either reset at the start of each Rx frame to a starting gain index, as specified in the
hopping table, or to continue from the previous receiver frame.
In the ADRV9001, the AGC configuration has the field "resetOnRxOn". For AGC to continue from the previous Rx frame, set resetOnRxOn to
FALSE. For AGC to reset to a starting gain index each frame, set resetOnRxOn to TRUE.
In FH, if the AGC is configured and the resetOnRxOn field is true, then the starting Rx gain for each frame is taken from the hopping table
instead of the resetOnRxonGainIndex field in the AGC configuration.
With manual gain control, the ADRV9001 programs the manual gain index for each frame based on the gain information in the hopping table or
through the DGPIOs.
The ADRV9001 allows up to 3 DGPIO pins to select the Rx gain or Tx attenuation for each hopping frame from a Rx gain or Tx attenuation
table with a maximum of eight entries. The GPIO pins formulate an index to the defined Rx gain or Tx attenuation table and the GPIO pins are
sampled at the hop edge. Then, the corresponding Rx gain index or Tx attenuation values are applied to the corresponding upcoming hopping
frames.
ORx Gain Control
The ORx gain operates in manual gain control. In this mode, set the desired starting gain index before enabling ORx. Update the gain
throughout the ORx frame by calling adi_adrv9001_ORx_Gain_Set() API.

SPECIAL FREQUENCY HOPPING OPERATIONS

Port-Based Frequency Hopping
As noted previously, all four channel ports (Rx1, Rx2, Tx1, Tx2) can be used in FH. However, these ports are not indicated in the hopping
tables. Instead, the channel enable pins are repurposed as channel setup pins to select the channels to hop upon. In the dual hop LO Retune
mode, there are also two hop signals to indicate when new frames start, one for each LO.
Each port is also assigned a controlling LO, which is fully configurable in certain FH modes. For example, LO1 controls channel 1 ports
(Rx1/Tx1) and LO2 controls channel 2 ports (Rx2/Tx2), or LO1 controls both receive ports (Rx1/Rx2) and LO2 controls both transmit ports
(Tx1/Tx2), or LO1 controls any other combination such as Rx1 and LO2 controls Rx2, Tx1 and Tx2.
Configure the LO assignment for each in the adi_adrv9001_FhCfg_t structure. In this structure, there are fields for the Rx ports (rxPortHopSig-
nals) and the Tx ports (txPortHopSignals). In these fields, each port can be assigned a "HOP" signal, where hop signal 1 is for LO1 and hop
signal 2 is for LO2.
NCO-Only Frequency Hopping
The ADRV9001 provides a numerically-controlled oscillator (NCO)-only mode, which is only used for Rx FH. By enabling this feature, it is
possible to define a non-zero rx1OffsetFrequencyHz or rx2OffsetFrequencyHz in the hopping table and those frequencies are applied to the
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