picoChip, Semtech to Enhance Femtocell Reference Designs

picoChip announced that it will be working with Semtech to enhance its market-leading femtocell reference designs with Semtech’s advanced packet timing solution. The addition of ToPSync(TM) to picoChip’s portfolio will enable support for those OEMs and carriers that have selected the IEEE1588 protocol. The two companies will work together to solve the challenging synchronization problems faced by operators implementing femtocell architectures to dramatically cut the cost and complexity of rolling out such networks.

Semtech and picoChip will jointly undertake field trials and performance evaluations to increase the functionality of picoChip’s complete, standards-compliant wireless reference designs. These include UMTS (HSDPA, upgradeable to HSUPA), cdma2000/EVDO and WiMAX/WiBro (both 802.16d and 802.16e) products. The companies will also engage in development activity connected with other advanced wireless protocols in which picoChip technology is being used. These include HSPA+, UMTS-LTE and TD-SCDMA.

“picoChip and Semtech both provide technology that meets a compelling need for the creators of real-world communications systems,” said Rupert Baines, VP Marketing at picoChip. “For cdma2000/EVDO and WiMAX the timing requirements are even more stringent that WCDMA and the extra precision of the Semtech solution is especially important. picoChip strives to provide flexible options for its customers and whilst our reference designs support all synchronization models, we see Semtech’s technology as genuinely unique and believe that together we can offer femtocell customers the timing solutions they require, more simply, at lower cost.”

Femtocells (sometimes known as home basestations or 3G Access Points) are small, low-cost wireless basestations intended for use in residential or corporate environments where high-speed coverage would otherwise be limited. The idea is established in the 3G community, but is now also arousing interest in cdma2000 and WiMAX/WiBro applications.

“picoChip is the industry standard architecture for WiMAX infrastructure, and the clear market leader in femtocell designs,” said Patrick Diamond, Director-Systems Engineering at Semtech. “We’re delighted to be working to integrate ToPSync technology into those successful platforms. The key to this success has been picoChip’s ability to offer a complete solution, particularly important in high-volume cost-sensitive markets where bill of materials costs are critical. Adding advanced synchronization capabilities is a major contribution to maintaining that integrated approach.”

3G networks traditionally rely on one of four techniques to achieve the tight timing they require (100ppb accuracy). Some use a precision crystal in each network node, but this approach is too costly for femtocells, which are inherently low-cost. GPS is a possibility, but is unreliable within buildings; precisely the environments for which femtocells are intended. Thirdly, the femtocell could use an external cellular network to supply timing, which is attractive assuming there is cellular coverage which there often will not be. Finally, traditional basestations use E1 backhaul connections to provide so-called Stratum clocks; this approach is unsuited to use in femtocells connected over residential broadband.

ToPSync(TM) technology can solve these problems by delivering a Stratum-quality clock via an ADSL/Ethernet connection, through a packet network. The advantage of the ToPSync(TM) synchronization solution for femtocells is that it only relies on the backhaul connection which must exist to implement the service. ToPSync(TM) implements synchronization over a Packet Network using IEEE1588, layering Precision Time Protocol (PTP) on top of native Ethernet (or other packet-based technologies) for transport.

This is achieved via a master node that takes the frequency and phase information from a highly stable and accurate clock source or GPS (PRC) and turns it into data. This information is then transmitted as sync packets over the network: the ‘slave’ nodes on the network receive these packets and use them to adjust their local time base to generate precise frequency and/or “time”, ie UTC.

picoChip is the leading supplier of silicon for femtocells, with customers that include Ubiquisys, ipAccess and a number of others. The company’s PC202 processor enables a single-chip modem, integrating all functionality for Node B, protocol stacks and interface software in one device. picoChip’s PC8208 software is the only HSDPA femtocell solution available today, and at 3GSM World Congress 2007 the upgrade to HSUPA was announced.

About picoChip
picoChip, located in Bath, England is dedicated to providing innovative, flexible wireless solutions to help equipment makers minimize time-to-market, costs, and system power consumption. The company has the most comprehensive reference designs in the industry, with complete, standard-compliant solutions for both UMTS (including HSDPA) and WiMAX (802.16d upgradeable to 802.16e).