User`s guide

Agilent PXT Wireless Communications Test Set
User’s Guide
181
SRVCC (Single Radio Voice Control Continuity)
SRVCC enables a VoIP/IMS call in the LTE packet domain to be moved to a legacy voice domain
(GSM/UMTS or CDMA 1x). For an operator with a legacy cellular network who wishes to deploy
IMS/VoIP-based voice services in conjunction with the rollout of an LTE network, SRVCC offers VoIP
subscribers with coverage over a much larger area than is typically available during the rollout of a new
network.
SRVCC functions as follows. As an SRVCC-capable UEe engaged in a voice call determines that it is
moving away from LTE coverage, it notifies the LTE network. The LTE network determines that the voice
call needs to be moved to the legacy circuit domain. It notifies the MSC server of the need to switch the
voice call from the packet to the circuit domain and initiates a handover of the LTE voice bearer to the
circuit network. The MSC server establishes a bearer path for the mobile in the legacy network and
notifies the IMS core that the mobile’s call leg is moving from the packet to the circuit domain. The circuit-
packet function in the IMS core then performs the necessary inter-working functions. When the mobile
arrives on-channel in the legacy network, it switches its internal voice processing from VoIP to legacy-
circuit voice, and the call continues.
Hardware and Software Requirements
Table 5-5: Hardware and Software Requirements
Hardware
Software Revision
License
E6621A PXT
6.4 or later
Agilent 8960 (E5515C/E) that is capable of running the
required software.
E6785I I.00.09 or
E6703I I.00.08 or
E6701J J.00.15
or later
E6785I (E6703I or
E6701J)
PC running Agilent E6966A IMS-SIP Client and Server
(or equivalent)
E6966A
Server:
3.1.0.7
Client:
3.0.0.19
E6966A-1FP
1
Audio Source
(for example: mp3 player)
N/A
N/A
UE that supports:
WCDMA or GSM
2
, LTE, IMS-SIP audio calls, and
SRVCC procedure
3
N/A N/A
1. This license enables you to run the client and the server on the same PC. Alternatively, the E6966A-2FP
license enables you to install an IMS client on an additional PC.
2. This procedure is described using a UE supporting WCDMA for ease and clarity. A similar procedure can be
developed using a UE that supports GSM.
3. The UE used in this procedure must have an embedded client.