Time Sync Analyzer — O-RAN

Introduction

The mobile network industry is moving towards an open, intelligent, virtualized, and fully interoperable Radio Access Network (RAN). Open fronthaul architectures and gNB disaggregation requires comprehensive analysis of RAN elements of O-RU, O-DU, and O-CU. The Radio unit (O-RU) needs to support RF and digital signal conversion, split 7.2x Low-PHY processing, and stringent time synchronization. Massive Multiple Input and Multiple Output (MIMO) and beamforming technologies for increasing spectral efficiency and energy saving for power and cost reduction add further challenges. As chipset vendors and NEMs roll out massive MIMO O-RAN Radio Unit (O-RU), they need to test O-RAN compliance, beamforming, and massive MIMO performance to guarantee the coverage, capacity, and user experience that is promised with 5G.

The Keysight Time Sync Analyzer (TSA), expanding Open RAN Studio solution portfolio, is a highperformance O-DU emulator that targets CUSM Plane test and validation for MIMO and massive MIMO O-RAN Radio Units. Driven by the Keysight Open RAN Studio application, it tests O-RU and chipsets with O-RAN 7.2x split compliant CU Plane stimulus generation and analysis, enables users to generate test vectors against a DUT, captures O-RAN uplink communications, and performs the measurements necessary to validate O-RU’s functional operation and performance with up to 600Gbps fronthaul throughput.

Keysight 5G Open RAN Studio — Solution Overview

Designed for 5G O-RAN Radio Unit (O-RU) testing, Keysight Open RAN Studio provides powerful, yet easy to use capabilities to emulate an O-RAN Distributed Unit (O-DU) — generate O-RAN compliant CUSM Plane test vectors, capture the DUT’s responses, and perform measurements that are needed to validate if the O-RU meets standard compliant operation and radio performance.

Open RAN Studio includes powerful O-RAN focused tools to construct, play, capture, and measure ORAN traffic over specialized hardware platform. Out of the box integration with Keysight’s PathWave Signal Generation and 89600 VSA software enables sophisticated 5G NR and LTE signal creation and analysis, extraction, and export of IQ vectors — for advanced modulation analysis of received RF / mmWave and radio performance. Additionally, when combined with Keysight Spectrum Analyzers and Signal Sources, the integrated Open RAN Studio solution delivers the most comprehensive cross domain, multi-channel RF / mmWave, and O-RAN protocol measurements that are available in the industry, for both FR1 and FR2 radios, downlink (DL), and uplink (UL) paths.

See the Open RAN Studio solution brief for further details.

Open RAN Studio for 5G O-RAN Radio Unit  (O-RU) testing

Open RAN Studio provides a test environment that includes and integrates with the tools, in both RF and Protocol Domains, to help you completely exercise an O-RAN CUSM compliant Radio Unit (O-RU).

To ensure measurement consistency between both RF and Baseband sides of the O-RU, Open RAN Studio software leverages the same industry leading 5G NR and LTE signal generation and measurement science that is used in Keysight spectrum analyzers and signal sources. This tight coupling ensures that CU Plane messages and baseband information match exactly with the signals that are captured on the RF side of the Radio Unit.