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Comprehensive Portfolio of DOCSIS 3.1 Test Solutions

24 July 2014 – Agilent Technologies announced a portfolio of Data Over Cable Service Interface Specification (DOCSIS) hardware and software test solutions for generating and analyzing signals up to a bandwidth of 192 MHz. The test solutions are used by R&D engineers to test transmitters, receivers and components against the requirements set forth in the DOCSIS 3.1 specification.

The DOCSIS standard continues to evolve to meet the needs of cable operators and their subscribers worldwide. Emerging applications, such as high-definition television (HDTV), video streaming around the home, and in-room gaming, are driving the demand for multi-gigabit data rates. This need for increased bandwidth has led to the development of version 3.1 of the DOCSIS standard.

DOCSIS 3.1 achieves its increased speed and capacity through the use of orthogonal frequency-division multiplexing (OFDM) and low-density parity-check (LDPC) forward error correction (FEC) technology. The new DOCSIS 3.1 specification provides:

o up to 50 percent more data throughput over the same spectrum;

o the ability to deliver 2.5 Gbps in the upstream; and

o 10 Gbps in the downstream on an existing hybrid fiber-coaxial (HFC) network.

DOCSIS 3.1’s efficient spectrum use enables a significant decrease in the cost per bit for data delivery. It provides a cost-effective way for cable operators to increase capacity and speed, providing them a competitive advantage over satellite and wireless providers.

“While the DOCSIS 3.1 standard delivers much needed capacity and speed improvements, it also creates a number of new challenges in design and test,” said Jay Alexander, Keysight Technologies’ chief technology officer, previously vice president and general manager of Agilent’s Oscilloscope and Protocol Division. “Agilent’s portfolio of DOCSIS 3.1 test solutions easily handles the complexity of OFDM and LDPC FEC, while at the same time supporting legacy DOCSIS technologies.”

Designing DOCSIS 3.1-based transmitters, receivers and components, and verifying their performance against the new standard, requires stringent testing. This process is made more challenging by the standard committee’s adoption of new technologies and the need for backward compatibility with previous DOCSIS versions. Agilent’s portfolio of hardware and software provides a complete DOCSIS 3.1 test solution required to address these technical challenges.

Signal Generation

For DOCSIS 3.1 signal generation, Agilent’s M8190A arbitrary waveform generator (AWG) features deep memory, up to 5 GHz bandwidth and excellent spurious-free dynamic range (SFDR). This enables the M8190A to realistically stress DOCSIS 3.1 signals up to 192 MHz bandwidth and perform transmission network testing over the existing HFC network.

Agilent’s M9099 Waveform Creator Application Software, combined with the M8190A AWG, creates uncoded DOCSIS 3.1 waveforms for component level tests. Agilent’s SystemVue electronic system level (ESL) design software provides a fully coded DOCSIS 3.1 transmit (Tx) and receive (Rx) simulation library. The library is used for generating waveforms with the M8190A AWG as well as conducting BER testing with low-density parity-check (LDPC) decoding. Additionally, SystemVue is the preferred platform for simulating stray signals to introduce as noise into the DOCSIS 3.1 transmission environment (e.g., LTE).

Signal Analysis

For DOCSIS 3.1 signal analysis, Agilent’s M9703A 8-channel AXIe high-speed digitizer, or its 2-channel PCIe version, the U5303A PCIe 12-bit high-speed digitizer, provides a wide-input frequency range (DC to 2 GHz). The channel interleaving capability enables a 4-channel configuration for the M9703A or 1-channel configuration for the U5303A. This allows the digitizers to capture DC to 1.4 GHz signals with exceptional dynamic range for DOCSIS 3.1 waveform acquisition.

Agilent’s 89600 Vector Signal Analysis (VSA) software supports multiple hardware platforms offering greater than 192-MHz bandwidth demodulation analysis capability. The 89600 VSA is widely used to test other OFDM technologies. SystemVue’s DOCSIS library and coded bit error ratio (BER) measurement capability is used to demodulate and decode DOCSIS 3.1 downlink signals.

For spectral measurements, Agilent’s N9020A MXA or N9030A PXA signal analyzers, with 160MHz bandwidth, offer tremendous capability for testing narrower bandwidth downstream and upstream DOSCSIS 3.1 signals.

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