Femtocell development and evolution trends

Rupert Baines, VP Marketing at picoChip, looks at some of the trends and developments in the femtocell market.

With recent figures released from ABI, the development of the femtocell market has been under particular scrutiny. No matter what the shape of the curve, it is clear that femtocells will live up to the hype, with volumes still expected to shoot up in 2010 and beyond.

The development of the femtocell market has seen some real milestones. During 2009 alone, seven operators launched femto cells for consumers: AT&T, DoCoMo, Optimus, SFR, Softbank, StarHub, and Vodafone. In addition to this, Sprint and Verizon in the US have been offering commercial solutions for far longer. These launches mean that many of the largest operators in the world are now deploying femtocells, and this is proof that femtocells are evolving from just a great idea to a reality. Despite its recent revision of market figures, ABI continues to forecast that by 2014 volumes will be hitting 40M units per annum.

Femtocell technology

Femtocell development has not been trivial as the femtocells themselves require the use of many new technologies if they are to operate satisfactorily. Accordingly operators have approached their deployments with care to ensure they "cover all bases" to give consumers confidence in the solution.

Long before the deployment stage, companies in the femtocell ecosystem were working on overcoming the substantial technological hurdles involved. In a domestic or enterprise setting, when a femtocell is switched on, it needs to detect its surroundings - searching for other base-stations in the surrounding area and then it needs to self configure itself to minimize radio interference to other cellular users in the vicinity.

Then the femtocell automatically connects to the core network via the broadband router.

In addition to this, as the femtocell is linked into the network, security, authentication and other services must be integrated into the device, adding further layer of complexity. The result is an end-to-end solution that offers a personal cell service in the home with perfect mobile voice coverage and high data rates, and all set up with no problems for the user.

Picochip implementation

To achieve the aims for femtocells, the internal silicon is the key. picoChip provides their chip bringing the core wireless capabilities into the femtocell. It is here that the greatest complexity lies.

A femtocell SoC, such as the PC3xx picoXcell, incorporates considerable processing power and accelerators to provide for the execution of the RNC stack functions. It also needs the right kind of processing power. It requires a blend of signal processing for the physical layer, and control plane and network processing for the stack. To satisfy these requirements, the PC302 includes both a PHY processing and an ARM 11 subsystem suitable for running the stack, provisioning and security.

Accordingly a PC3xx picoXcell device integrates all of the baseband processing needed for a femtocell, plus many of the requirements defined by the established standards for the femtocell industry. The device deals with digital samples to and from RF, and provides a complete signal processing chain that enables them to be passed via a broadband connection to the operator network.

Although they are much smaller, and look less complicated, Femtocells actually include far more intelligence than traditional base-stations. Because of this change in the way tasks are partitioned in the network, femtocell chips like the picoXcell family need to provide enhanced security features for authentication, location detection, encryption and the prevention of DoS attacks.

Femto cell market evolution

The first launches from Sprint & Verizon were relatively simple, with a 2.5G service and the rationale of providing simple voice coverage to improve customer retention. Vodafone and AT&T's moves are more sophisticated; with HSPA femtocells reducing churn while improving voice and data coverage and capacity.

Now the femtocell market is maturing rapidly. The initial technical challenges of implementing the baseband and protocol stack in an integrated device with low power dissipation were essentially solved by 2007. The following year was about more subtle issues such as interference management and security. Just as important was the definition of standards that ensure any femtocell can integrate with the network.

The year 2009 saw productization of the femtocell and initial launches. It was the year the technology became real to consumers. As a consequence, we are beginning to see the market move into a different phase; that of becoming a consumer market with a value chain like those in the DSL and Wi-Fi sectors.

During 2010 and 2011 we expect to see the operator business cases established, widespread deployments and cost optimization, as volumes dramatically increase. The predicted 40M units estimated by ABI represents a significant increase in volumes from the 350,000 of 2009.

As volume increases, costs will be driven down. The target $20 chipset ASP, of course, requires technical excellence, but ever increasing functionality will be expected as well. The early pioneering spirit will need to be supplemented with less glamorous but no less important values of operational excellence. The femtocell ecosystem needs to ensure that it offers certified quality, a reliable supply chain and logistical support - in short, that it delivers on its promises.

As efficiencies begin to emerge, the femtocell market will consolidate and simplify. At picoChip we have anticipated this by creating a 'complete femtocell solution' including expanded functionality within our femtocell chips. This concept enables a single pre-integrated and optimized system that includes all the software modules for the complex control functionality required by femtocells. While some companies have chosen to develop the femtocell software code themselves, many others are looking to purchase a complete solution. picoChip's reference solution addresses all of the key 'pain points' experienced by OEMs and ODMs when developing and building femtocells, such as interference management, security, timing and provisioning.

This complete femtocell offering goes significantly beyond silicon, making overall systems integration far easier and more cost effective. This bundling will eliminate the need for femtocell makers to buy-in separate software or invent it in-house - increasing flexibility and dramatically reducing time to market. It will also empower femtocell makers to build in additional features, applications and complexity.

Future femtocell development

The femtocell market is undergoing a period of radical change and development. Market participants must keep pace with this. picoChip believes one way of doing this is by incorporating as much functionality as possible onto the femtocell chipset to make it easier for OEMs and ODMs to quickly develop femto cells and manufacture in volume. An inevitable consolidation of the market will take place as volumes ramp up, as it has done in the past with WiFi and DSL. It is crucial that the market is prepared for these changes or rapid femtocell development and evolution in order to benefit everyone in the value chain.

Rupert Baines is VP Marketing at picoChip. The company was established in 2000 and provides technology products that enable new types of cellular communications service and improve existing services. Their key technology, experience and expertise are in the design and deployment of femtocells for use in residential, enterprise, rural and metropolitan environments.