DMTS™-9201

LTE L1/L2 Layer Tester

For wireless Network Equipment Manufacturers, the Dyaptive DMTS-9201 is the industry platform for testing the LTE L1/L2 layer functionality and performance. 

The 3GPP Long Term Evolution (LTE) standard is expected to increase significantly the mobile user experience through improvements in data throughput and user plane latency compared to previous wireless standards. These improvements require significant changes in parts of the network infrastructure and mobile user equipment, especially at the physical layer of the protocol. In LTE more complexity has been moved from the network into the eNodeB to achieve higher data throughput and lower latency.

The performance of the LTE network will greatly be affected by the design and performance of the eNodeB scheduler. In order to properly validate the operation of the scheduler, test equipment must enable users to control the various inputs into the scheduler algorithm that affect the network’s behaviour such as channel quality and Quality of Service. Furthermore, test equipment must provide the ability to analyze or monitor key performance indicators (KPIs ) such as spectral efficiency throughout the execution of the test case. As the scheduling complexity increases with the number of active bearers, the scheduler must be tested with test equipment that scales up to the maximum number of mobiles per sector. With repeatable and deterministic test cases, designers and testers can compare KPIs associated with varying user load, different scheduler algorithm implementations, different eNodeB configurations and /or different channel conditions in order to ensure that system requirements are met.

The DMTS-9201 incorporates a number of test modes that allows an incremental approach to develop and test individual LTE layers from the PHY layer upwards. It enables the user to test downlink and uplink functions independently, and verify the performance under load.

Expandable:

• The only LTE solution that provides hundreds of simultaneously active UEs instances per cell within a single platform
• Up to 32 2x2 MIMO sectors

Flexible:

• Verify BCH, PCH, RACH, downlink and uplink transport channels as well as radio-bearers individually or running them simultaneously
• Analyze PHY layer and real-time operation of Downlink and Uplink physical data channels under HARQ retransmissions.
• Test Scheduler algorithm that maximizes spectral efficiency and high Quality of Service with the least number of channel resources used under various channel conditions.
• Track scheduling decisions along with optimization within sub-frames.
• Identify the modulation schemes under various channel conditions.
• Monitor scheduler algorithm and resource allocation during perfect and worst condition.
• Perform ARQ and HARQ analysis in conjunction with CQI modifications.
• Measure Spectral Efficiency over time as a percentage of the maximum data rate.
• Analyze PDCCH resources under various channel conditions (CQI) to balance transmission failures vs channel loading.
• Show Number of UEs scheduled per TTI and determine the optimum level of number of UE per TTI vs spectral efficiency.
• Verify that the correct Aggregation Levels are used for a specific DCI format under various channel conditions.
• Control test setup with the Dyaptive Workbench, leveraging our multi-UE implementation of PHY, MAC, and RLC layer
• Flexible framework provides ability to create test cases using our Layer 1 and 2 implementation to test timing performance and resource allocation
• Control UE capabilities, frequency bands and operating environment to more precisely model real-world scenarios

Reconfigurable:

• Upgrade the DMTS-9201 L1/L2 Network Tester to a fully operational DMTS-9200 running RRC, NAS and data applications

Insightful:

• Understand access network performance from UEs perspective, with logging across multiple layers of the protocol

Predictable:

• Leverage an automated test environment that provides repeatable and deterministic tests

Key Features & Benefits

• Hundreds of UEs engaged in coordinated or random traffic scenarios simultaneously
• Verify Scheduler performance and resource allocation
• 2 x 2 MIMO
• Support for 1.4MHz, 3MHz, 5MHz, 10MHz, 20MHz
• Up to 150Mbps transfer rate on the downlink and 50Mbps on the uplink

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Integrated Test Functionality

Traffic Generator	Mix channel types Spread traffic across hundreds of UEs, or concentrate in a few Define individual UE or group behaviour Randomize traffic models simulates variety of real-world conditions QoS selection and measurement Continually take eNodeB to maximum load through extreme stress conditions over many days Verify base station power consumption and RAM alloaction under load
Scheduler Performance	Measure Scheduler performance and analyze resource allocation
Channel Emulator	Control radio channel impairment to simulate variety of propagation environments
Performance Analyzer	Analyze performance with a powerful visual data mining tool Enable correlations between logs generated from various levels across all protocol stacks Generate graphs for various metrics e.g. Modulation scheme vs Resource Blocks or CQI

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Software Defined Radio (SDR)

As with our 1xRTT, EvDO, UMTS and LTE Network Tester, the DMTS-9201 employs a unique application of SDR technology. The DMTS-9201 system produces an enormous offered UE capacity and allows users to control and coordinate mobile behavior and RF conditions, as well as define and run tests that are completely repeatable. Because the system is software based, it is easily upgradeable and reconfigurable, as well as scalable protecting customers investment in their test system.

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Configurations

The DMTS-9201 can be deployed in multiple configurations. It can scale from a single blade processing element supporting hundred mobiles, up to 80 blade processing elements, and for up to 32 eNodeB MIMO capable sector ports.

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System Management for Test System Automation

• Dyaptive Workbench (GUI)
• Quick set up and installation
• Test case creation, management and launch pad
• Configure sectors, carriers and UARFCN
• Real time statistics
• Performance analysis
• Manage user accounts and software licenses
• Multiple user support
• Backup / restore database

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User Controls for Call Models and Simulation

System Configuration
Sectors	1 to 32 MIMO sectors Multiple sector-carriers (cells)
Test Terminal Identities & Behavior	Statistical behavior of test terminal population Coordinated or random behavior
Test Conditions & Triggers	Terminate tests based on time or statistics Configurable Pass/Fail criteria
Logging	Physical Layer parametric measurements OTA Signalling Filters
Traffic Model
Test Terminal Control	Registration rates Traffic rates up to 100,000 connections per hour
Traffic (data) Rates	Downlink: up to 150Mbps Uplink: up to 50Mbps
Radio Environment Control
	Pilot strength (Path Loss) HARQ, CQI, RI, PMI control
Statistics Collection
	Statistics can be viewed and analyzed per test terminal, test terminal group, cell, sector and per Base Station Physical Layer statistics BLER CRC errors RACH attempts OVSF code overlaps Resource Block usage Real time call and data transfer statistics Registrations (attempts, success) Access (attempts, success)
Air Interface Standards
	UE Radio Access: 36.306 PHY: 36.101, 36.211, 36.212, 36.213, 36.214 L2/L3: 36.321 (MAC), 36.322 (RLC)
RF Support
	RF Bandwidth 1.4, 3, 5, 10, 15, 20 MHz Bands Supported:
Uplink Downlink Band 1 1920 - 1980 MHz 2110 - 2170 MHz Band 2 1850 - 1910 MHz 1930 - 1990 MHz Band 5 824 - 849 MHz 869 - 894 MHz Band 13 777 - 787 MHz 746 - 756 MHz Band 18 815 - 830 MHz 860 - 875 MHz