User's Manual

5. Installing the Remote Link

EAC-2100 Manual: (Draft, 02/01) Page 6-2

6.3 Handoff from EAC to a cell adjacent to the donor

Handoff from the EAC-2100 to adjacent cells happens almost automatically because of

the fundamental role of the subscriber unit in the TDMA handoff process.

When a call is operating on the EAC-2100, the MAHO reports from the subscriber are

repeated back to the donor. The donor compares the RSSI reports from the adjacent

cells to the “current RSSI”. If the RSSI from the adjacent cell is better by a sufficient

amount, the donor will do the handoff. The only role the EAC-2100 has is to accurately

repeat the MAHO information back to the donor, and it does this. The donor does not

realize that the “current RSSI” that the mobile is reporting is really coming from the

EAC-2100, however, that does not matter. It is still proper for the call to be handed off

to one of the cells adjacent to the donor if that cell can handle the call better than the

EAC-2100.

No adjustments or parameters in the EAC-2100 will affect or control this handoff case.

The EAC-2100 does monitor for handoff messages sent by the donor, and these

occurrences are reported in the “SCS” screen and in the “DCS” call statistics.

6.4 Handoff from donor to EAC – “Hand-in”

Calls that are operating on a donor DTC channel are handed in to the EAC by the

following process:

- The EAC uses an available TDMA board to keep track of the average RSSI

from mobiles on donor DTC channels.

- As the subscriber gets closer to the EAC coverage area, the average RSSI will

exceed a preset threshold. The EAC will then periodically decode the data

coming from the subscriber unit and extract the DVCC and MAHO

information.

- If the DVCC is correct, the EAC will attempt to hand-in the mobile when

BOTH of the following conditions are met:

The RSSI at the subscriber from the donor must be weaker than the level set in the

EAC parameter:

“HANDIN THRESHOLD – DTC – LOAD SHED LEVEL”

AND

The RSSI at the portable from the EAC must be better than the RSSI at the

subscriber unit from the donor by:

“HANDIN THRESHOLD – DTC – MINIMUM IMPROVEMENT”.