Dual-Band Digital Optical Repeater
DW-010-7373-08
Installation & Operation Manual -
Preliminary
Dali Wireless
Proprietary and Confidential
40
Rev: 0-2
Feb 2011
0
5.3.3 Delay Measurement and Control
Each DAU and DRU inside Dali’s DOR network supports manual delay adjustment of up to 160 us (step size 0.1
us).
In addition to manual delay adjustment/equalization, Dali’s DOR offers fully automated Delay Equalization
function
The optical delay between DAU and DRU’s that are part of the star network is evaluated by measuring the time
required for a test pattern to reach the DRU and loop-back to DAU time measurement block.
The optical link delay between the DRU’s connected in a daisy-chain (DRU1 to DRU2, DRU2 to DRU3, …), is
evaluated in a step-by-step process starting with measuring delay between DRU1 and DRU2, then delay between
DRU2 and DRU3, and so on, until all fiber link delays are measured. Information about link delays is
communicated to the DAU via the M&C channel.
The DAU master micro processor then calculates the amount of additional delay that should be applied to each
DRU in the network (UL and DL path), using fiber link delay measurements and knowledge about fixed delays
introduced by baseband and RF processing. The time delay to each DRU in a network is then equalized by the
DAU sending a command to each DRU to set its DL and UL delay to the desired/calculated value.
Figure 5-8 Delay Measurement Process
FPGA
DAU
FPGA
DRU1
FPGA
DRU2
SFP1
SFP2
SFP3
SFP4
SFP5
SFP6
SFP1
SFP2
SFP1
SFP2
uP
Ethernet
Wireless
Modem
CommScope v. Dali Wireless
IPR2020-01409
DALI WIRELESS Exhibit 2003
Page 40 of 60
