The requirement today is for protocol testers that support both legacy as well as the latest protocols, since mobile networks have become hybrid
By Sneha Ambastha
Technological advances in protocol testers are continuously being made to meet new wireless standards and future market demands. Communication forms the backbone of mobile radio technology and in order to keep it running, powerful mobile radio testers with an ability to simulate complex real-world network scenarios are needed. Manufacturers of LTE chipsets and wireless devices use protocol test solutions during the early phases of development to thoroughly check their implementations. The focus is on tests that help ensure that the basic functioning of the protocols on the air interface complies with 3GPP specifications. In later development phases, engineers should also address performance aspects, e.g., the data throughput of LTE wireless devices that is measured under various propagation conditions. Depending on the integration of the protocol layers, there are various approaches to protocol testing.
Protocol testing equipment are used by design engineers, quality engineers, validation engineers, test engineers, application engineers, etc.
Technologies at hand
Increasing test demands and quick standardisation of protocols across mobile computing designs have opened up the space for tools capable of complex protocol analysis. Multiple modules responsible for testing various protocols are being integrated into the same hardware. The options to connect multiple hardware for greater flexibility have also increased.
The configuration and the dynamic behaviour of the layers are defined by the 3GPP test specification or by user-defined test scenarios. This allows any signalling scenario to be tested and reproduced. The latest tools used for protocol analysis are designed to support 3GPP test specifications or features not only up to Release 12, but are also enabled for any of the future releases.
Mobile network protocol analysers, also known as signalling protocol analysers, are important tools to trace the cause of failures. They are used to verify diagnoses, and to improve the network quality and the user experience.
The requirement today is that protocol analysers must support both legacy as well as the latest protocols since mobile networks have become hybrid. Some of the networks are 2G, whereas some are a combination of 2G-3G and now we also have 4G cellular technologies. Today, we also have Ethernet protocol analysers for networks that are migrating to IMS or an IP based network architecture.
Rather than developing new protocol testing equipment, the industry is more focused on upgrading the existing protocol testers with new software and features.
How to select the right model
While making a decision on which protocol analyser to buy, it is just not enough for buyers to map their requirements with what is supported today, out-of-the-box. As wireless technologies are evolving and market trends are changing dramatically, it becomes very important to ensure that the product you buy is future-proof to a certain extent at least, and is aligned with your future requirements. Here are some points that need to be considered while buying a wireless communication tester for protocol analysis.
- It should support multiple technologies (cellular and non-cellular) with a Layer 1 to Layer 3 stack implementation.
- It should have a future-proof, powerful RF hardware to support all 3GPP defined bandwidths and technology beyond 3GPP Rel-12.
- It should have a development environment for signalling scenarios with automatic configuration of the layers below.
- It should be capable of faster error analysis and debugging.
- It should have modular and flexible hardware.
- It should support local applications and repair, and allow calibration service.
Devices available in the market for protocol analysis
Model: R&S CMW500, Brand: Rohde & Schwarz, Manufacturer: Rohde & Schwarz GmbH & Co. KG
R&S CMW500 is a wide band radio communication tester from Rohde and Schwarz, developed to support both current and future wireless standards keeping in mind the continuous technological advancements and growing market demands. It can be used for testing all protocol layers – from the RF to end-to-end application tests. The company claims that it includes all the technologies, so only a single device is enough to test the handover between different technologies. It also supports LTE-Wi-Fi offloading and coexistence tests because of its capability to support both LTE and WLAN.
Key features
- Supports multiple cellular wireless standards like LTE/LTE-A, WCDMA/HSPA+, GSM/EDGE and associated inter- RAT measurements
- Supports non-cellular and broadcast technologies like WLAN, BT, GPS, DVB-T (Layer 1 testing)
- Capable of maximum data rates (CAT 7), and supports multiple inputs and multiple outputs (MIMO) with multi-cell capability
- Allows module tests, system and integration tests, regression tests, conformance tests and network-operator-specific tests
- Saves a lot of space being a single box tester and hence reduces costs
- Has an inbuilt fading functionality to test the fading scenarios without any additional instrumentation
USP: The spectrum of measurements and tests spans all protocol layers, from the physical layer to U-plane applications
Contact details: Ph: 01142535400, [email protected], www.rohde-schwarz.com
Indian branch: Rohde & Schwarz India Pvt Ltd
Model: ME7834, Brand: Anritsu, Manufacturer: Anritsu Corporation, Japan
ME7834 is a mobile device test platform from Anritsu, registered as GCF TP119 and is capable of tracking TS 36.523 for LTE and TS 34.123 for UTRAN. It can address development and conformance applications, and can evolve to provide advanced system simulation. It allows parallel testing, minimising system utilisation and reducing the testing time by up to 40 per cent. This third generation mobile development program enables LTE development teams to accelerate their designs and stay competitive.
Key features
- Supports LTE-advanced for releases 8, 9 and 10
- Supports high-performance LTE network simulation for UE Categories 1 to 4 and 6
- Supports both FDD and TDD network simulation
- Supports VoLTE-required features
- Supports protocol test needs from 1 LTE cell to 4 LTE serving, MIMO cells with additional neighbour cells
- Supports up to three parallel test controllers for simultaneous testing
USP: Provides flexible protocol test solutions throughout the lifecycle of modern wireless terminals
Contact details: Ph: +91-80-40581300, [email protected], www.anritsu.com
Indian branch: Anritsu India Pvt Ltd
Model: U4431A, Brand: Keysight, Manufacturer: Keysight Technologies, USA
The U4431A is a MIPI M-PHY protocol analyser from Keysight that supports the analysis of multiple M-PHY buses simultaneously. MIPI M-PHY standards form the backbone of next-generation mobile computing designs and today, multiple high-speed buses are being implemented into the mobile designs to manage multiple high-resolution cameras, high-speed peripherals, advanced graphics adapters and massive memory buffers. The U4431A offers up to 16GB of analysis memory on each lane, enabling designers to capture tens of seconds of system traffic, even at high speeds.
Key features
- Capable of tracking multiple M-PHY buses from the PHY to the application layer
- Supports up to HS Gear3 data rates, up to 16GB trace depth and up to four data lanes
- Supports raw mode 8b/10b data views and N-way trigger branching
- Supports the transaction level decode view for insights from signals to the application layer
- Supports performance analysis view for optimising designs
- Comes with a packet generation option for conformance and compliance testing of UniPro and UFS
USP: Accelerates M-PHY products with deep insight across the entire design
Contact details: Ph: 1800 11 2626 (toll free) or 0124 229 2010, [email protected], www.keysight.com
Indian branch: Keysight Technologies India Pvt Ltd
