Clear Requests Sent on the A interface (TCH) (Signaling Channel)

Measurement Counter

CM369:CELL_A_CLR_REQ_TCH_SIG

Description

After the MS seizes a TCH to carry signaling, the BSC sends a CLR REQ message to the MSC if the BSC releases a call due to various causes.

This measurement provides number of clear requests sent on the A interface when the channel type is TCHF or TCHH and the service type is signaling channel.

Unit

Integer number or integer.

Measurement Point

When a TCH is seized as a signaling channel during a call, this counter is measured when the BSC sends a CLEAR REQ message to the MSC.

This counter is calculated at A5, as shown in Figure 1.

Figure 1 Call drops in the immediate assignment (including very early assignment) procedure

A1: Call Drops Due to ERR IND Received in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the ERR IND Received on the TRX in the Overlaid Subcell in Stable State

A2: Call Drops Due to the CONN FAIL IND Received in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the CONN FAIL IND Received on the TRX in the Overlaid Subcell in Stable State

A3: Call Drops Due to REL IND Received in Stable State, Call Drops Due to the REL IND Received on the TRX in the Underlaid Subcell in Stable State, Call Drops Due to the REL IND Received on the TRX in the Overlaid Subcell in Stable State

A4: Call Drops Due to No MRs from MS for a Long Time, Call Drops Due to No MR from the MS on the TRX in the Underlaid Subcell, Call Drops Due to No MR from the MS on the TRX in the Overlaid Subcell, Call Drops due to Abis Terrestrial Link Failure, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Underlaid Subcell, Call Drops Due to Abis Terrestrial Link Failure on the TRX in the Overlaid Subcell, Call Drops Due to Equipment Failure, Call Drops Due to TRX Failure in the Underlaid Subcell, Call Drops Due to TRX Failure in the Overlaid Subcell, Call Drops due to Resource Check, Call Drops Due to Resource Check on the TRX in the Underlaid Subcell, Call Drops Due to Resource Check on the TRX in the Overlaid Subcell

A5: Clear Requests Sent on the A Interface

A6: Call Drops Due to Forced Handover, Call Drops Due to Forced Handover on the TRX in the Underlaid Subcell, Call Drops Due to Forced Handover on the TRX in the Overlaid Subcell

A10: Successful SDCCH Seizures (Call Type)

Formula

Clear Requests Sent on the A Interface (TCH) (Signaling Channel) = [Clear Requests Sent on the A Interface (TCHF) (Signaling Channel)] + [Clear Requests Sent on the A Interface (TCHH) (Signaling Channel)]