A simpler solution to home A/V

It would be hard to understate the impact wireless connectivity has had on the transport of all kinds of data, but it seems there are still some things that are better done with wire, particularly in home entertainment systems. There is currently no sign of a universal solution for streaming HD content wirelessly from an STB to a TV or surround sound system, for example. Invariably these applications still employ (separate) cables to achieve what is often a one-time installation.

The growing consumption of on-demand content becoming available from an increasing number of providers also highlights the need to extend internet connectivity to home A/V equipment that isn’t necessarily equipped with a wireless interface. Bridge technologies such as PLC are increasingly being used to distribute wire-based internet connectivity to consumer devices around the home, at least to those that are equipped with an Ethernet port. A natural extension of this, already being deployed in increasing volumes in the commercial and light industrial sector, is PoE, which can now supply as much as 50W over standard Cat5 (or above) cable. It allows appliances with modest power demands to be powered and connected using a single connector over standard and low-cost cable.

It’s not too surprising to find that this same approach has also been applied to the home, but with even greater focus on the use-case. A technology called HDBaseT allows uncompressed HD video content, audio, Ethernet connectivity, power and control functions to be transmitted and received over Cat5e/6 cable. For this reason the technology is marketed under the name ‘5Play’, as it brings all five features together in a single solution. However, just like any other sector and any other solution, it has direct competition from an alternative proposition, and in this case it’s Audio Video Bridging (AVB).

Future proof

Part of the philosophy behind HDBaseT is to support tomorrow’s technologies and it does this, in part, by supporting full HD, 3D, 2K and 4K content which can be streamed uncompressed to a network of devices or simply point-to-point. It uses a proprietary phase amplitude modulation protocol in an asymmetric way, which allows it to cover distances of up to 100m, while supplying as much as 100W of power, 100Mb Ethernet, and control signals using RS232 and USB protocols. The latest version of the specification, HDBaseT 2.0 introduced a feature set called HomePlay; building on 5Play, it adds point-to-multipoint connectivity, multi streaming and switching capabilities.

However, while the features of 5Play, such as PoE, can be implemented with a range of discrete solutions, full SoC support for HDBaseT is less common. Valens, a semiconductor vendor focussing exclusively on HDBaseT - and co-founder of the HDBaseT Alliance - recently introduced its Colligo family, a second-generation chipset which supports HDBaseT 2.0, but it remains alone in offering a complete SoC, and only a few semiconductor vendors have joined the Alliance.

The main competition for HDBaseT appears to be AVB, which has wider support within the semiconductor industry, primarily because of its greater scope and because it’s based on a more conventional version of Ethernet. The organisation championing AVB, the AVnu Alliance has, in the opinion of some, achieved significant developments in recent years to improve the position AVB in the overall market.

There will be tens of millions of AVB ports, believes Vitesse’s Brian Jaroszewski

According to Vitesse Semiconductor’s Senior Product Marketing Manager, IP Licensing, Brian Jaroszewski, AVB got off to a shaky start but now shows great promise. Standardisation has played a massive role in building confidence in AVB, as has the establishment of interoperability testing; even if a design complies with the Ethernet standard, it can still fail in the field, according to Jaroszewski. Perhaps more significantly is the AVnu Alliance’s focus on cracking the automotive market. It has now developed a Marketing Requirements Document for the automotive market; a significant step, according to Jaroszewski. AVB can also support Time Sensitive Networking, which elevates its performance for time critical data.

Vitesse is known for its promotion of all things Ethernet, so perhaps it’s no surprise to learn that it favours AVB, but the real reason is the opportunity; Jaroszewski believes that as AVB moves in to the automotive sector demand will increase massively. This will mean that, while HDBaseT may have thousands of ports, there will be tens of millions of AVB ports. Vitesse is already planning to meet this demand with its hardware and software solutions, including IP.

Microsemi, which is a member of the HDBaseT Alliance (but not listed as a member on the AVnu Alliance website), is a firm proponent of PoE and has several product offerings. Microsemi’s VP of Business Development, Daniel Feldman, pointed out that HDBaseT doesn’t require any algorithms for compression and decompression of video, adding: “For an Ethernet-based standard to displace HDBaseT it needs to include a definition on what video compression standard is used and how a video session starts/stops. HDBaseT turns the Cat5e cable into just a long HDMI 1.4 pipe, which from a video connectivity point of view is much simpler.”

HDBaseT is a ‘much simpler’ solution to streaming HD content over Cat5e cable, says Microsemi’s Daniel Feldman

And simplicity seems to be the crux, particularly in the consumer market. Support for HDBaseT is now appearing in consumer TVs (LG Electronics, Sony and Samsung are three of the four top-level members of the HDBaseT Alliance, alongside Valens), so it’s possible its future is assured. Vitesse’s Jaroszewski stated that, although it has an overall strategy for AVB, if HDBaseT maintains or improves its current position it could also have a place in its product portfolio.