Real Time

Closed Loop Test Settings

This topic provides information on the closed loop settings located in the LTE Clause 8 test list under the Common Settings node. These settings configure how the instrument reacts to the input feedback signal configured in the instrument node and explained in the Closed Loop Feedback Configuration topic.

Markers

Makers provide an output signal to indicate when an event has occurred or to trigger an internal function. Each marker provides the same selections, but each marker can be set differently.

None	No Marker signal.
Frame Pulse	Pulse at every 10 ms LTE radio frame
Sub-Frame Pulse	Pulse at every 1 ms LTE subframe
Slot Pulse	Pulse at every 0.5 ms slot
Round Trip Time Pulse	indicates the HARQ round trip time LTE FDD—the timed pulse of 8 ms is synchronized to the process number LTE TDD—the pulse cycle depends on the UL/ DL Configuration value
HARQ State	High for HARQ ACK received subframe Low for HARQ NACK received subframe
ALC Control	ALC signal to control RF output of the signal generator
RF Blank	RF Blank signal to control RF output of the signal generator
Timing Adjustment Command	Echo back of the received timing adjustment command (RS-232 serial data)
Timing Adjustment State	Indicates timing adjustment operation state
SFN Pulse	Pulse at every SFN 10.24s cycle
AUX0...AUX15 Monitor	Monitors the specified AUXn input signal. The timing of this output marker signal is not specified. This signal is available only to confirm that the AUX signal is being received on the expected port.

HARQ/TA Settings

The settings in this section tells the PXB or Signal Generator (instrument nodes) when to respond to the received feedback signal. The settings are the same for LTE FDD and TDD with the exception of the HARQ-ACK Input Sampling Position property. For LTE TDD, this property is inactive (grayed out).

For information on each setting, use the hints that appear when a property is clicked.