Diversity Mode; Frequency Hopping With Rx/Orx Gain Control - Analog Devices ADRV9001 User Manual

Reference Manual ADRV9001
FREQUENCY HOPPING
Figure 123. ORx Timing with Tx Setup with PLL Mux Mode

DIVERSITY MODE

The ADRV9001 supports the diversity mode in FH. However, there might be more timing constraints to consider.
Basically, the ADRV9001 requires increased time to prepare for an upcoming frame if two channels are enabled, this increased time must be
taken into consideration.
To enable two channels for diversity, the operation is like a 1T1R use case. However, control the setup signal for both channels. Prior to the first
hop edge, set channel 1 setup rising edge and channel 2 setup rising edge high. There is no restriction on when these signals come relative to
each other. However, the last one set should be 1 μs prior to the hop edge.
Figure 124. 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.
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