ANRITSU CORPORATION is proud to announce its support for industry first verification of 3GPP RAN5 Rel18 NR LTM testcases on its 5G NR Mobile Device Test Platform ME7834NR.
In mobile networks, the primary objective of handover is to ensure that user equipment (UE) remains continuously connected to the cell offering the best radio conditions. As users move, the network must transfer the UE from a serving cell to a neighbouring target cell with minimal interruption to ongoing data transmission and reception.
In current 5G deployments, handover is typically initiated by the base station via a Radio Resource Control (RRC) message. As RRC operates at Layer 3 (L3), this procedure – commonly referred to as an L3 handover – introduces a brief service interruption. Even in well optimised networks, this interruption is typically in the range of 50–90 milliseconds. While acceptable for many broadband use cases, this latency becomes a limitation for emerging time critical communications (TCC) and extended reality (XR) services, where even short disruptions can degrade user experience.
To address this challenge, 3GPP Release 18 introduced Lower Layer Triggered Mobility (LTM), a new mobility mechanism that enables the network to trigger handover using Layer 2 signalling, based on Layer 1 measurements performed and reported by the UE. By leveraging lower layer information, the UE can synchronise in advance – both uplink and downlink – with a neighbouring cell designated as an LTM candidate cell.
This proactive approach significantly accelerates the handover process, reducing execution time, signalling overhead, and service interruption. As a result, LTM delivers more seamless mobility, supporting the stringent latency and reliability requirements of next generation 5G applications and paving the way for advanced services in high mobility and dense network environments.
Through this initiative, Anritsu is supporting the industry’s verification of LTM conformance and interoperability, helping accelerate commercial implementation of 3GPP Release 18 features.
“Support for 3GPP Release 18 NR Lower Layer Triggered Mobility test cases enables significantly faster and more reliable handover performance, which is critical for time‑sensitive and immersive 5G services,” said Daizaburo Yokoo, General Manager of Anritsu’s Mobile Solutions Division. “By enabling accurate verification of LTM functionality, Anritsu supports operators and device vendors in reducing handover interruption, lowering signalling overhead, and delivering a more seamless user experience – even in highly mobile scenarios.”
“We are proud that this milestone enables the industry to implement and validate advanced 5G mobility enhancements such as Release 18 LTM quickly and with confidence,” he added. “This milestone supports the evolution of 5G Standalone networks towards applications that demand ultra‑low latency and high reliability.”
