Freescale DSP family delivers new levels of performance for the next wave of wireless base station deployments

Freescale’s new MSC8157 and MSC8158 products are the next generation of the widely deployed MSC8156 DSP. The new DSPs are based on Freescale’s SC3850 core running at 1.2 Ghz, which recently earned the highest BDTIsimMark2000™ fixed-point performance score of any DSP architecture tested to date by independent signal-processing firm Berkley Design Technology, Inc (BDTI).

The MSC8157 product supports a broad array of 3G and 4G wireless standards, while the MSC8158 is cost-optimised to enable more efficient and higher throughput deployments for WCDMA networks. Both products help lower bill of materials costs by integrating technologies that eliminate the need for additional, costly ASICs and FPGAs required in competing solutions.

“With the introduction of the MSC8157/58 product family, Freescale leverages its deep understanding of wireless networking technology to address the needs of service providers to dramatically reduce network costs while increasing bandwidth,” said Lisa Su, senior vice president and general manager of Freescale’s Networking and Multimedia Group. “These new products balance leadership performance, cost and energy efficiency to meet the needs of next-generation 3G/4G networks.”

As the industry migrates to higher-speed, lower-latency, data-centric 3G-LTE mobile networks, OEMs increasingly demand DSPs that deliver higher throughput to address growing base station computational complexity. Freescale’s newest DSPs meet this demand with an enhanced version of its MAPLE-B baseband accelerator. The flexible MAPLE-B2 accelerator packs a high level of throughput in a small area of silicon, optimising for cost and power while providing extremely low-latency implementations of advanced antenna processing algorithms.

The MSC8157 and MSC8158 DSPs offload many mathematical and baseband intensive tasks to the enhanced MAPLE-B2 block, freeing the processors’ six cores to handle other tasks. For example, floating-point MIMO processing is handled by the MAPLE-B2 block, significantly improving latency over floating point DSP core implementations. The MAPLE–B2 block additionally provides OEMs a single hardware platform that supports multi-mode operation and allows for the adoption of additional standards with a simple software switch. This flexibility facilitates the creation of highly scalable equipment that helps service providers reduce costs, lower capital expenditures and boost throughput.

“Freescale’s new MSC8157 and MSC8158 DSPs take an innovative systems-level approach in addressing the unique power, performance and cost requirements of the wireless communications equipment market,” said Will Strauss of Forward Concepts. “This systems-level mindset reflects the company’s long track record of supplying the world’s top networking equipment manufacturers with its QorIQ and PowerQUICC lines of microprocessors.”

Technical features

· The MSC8157 delivers the peak throughput possible in 3G-LTE 20 MHz bandwidth, delivering 300 Mbps in the downlink and 150 Mbps in the uplink, with 4x4 DL and 2x4 UL MiMO, as well as various interference cancellation schemes to support hundreds of users. The DSP also supports multiple WCDMA sectors of 42 Mbps in the downlink and 11 Mbps in the uplink, together with multi-mode simultaneous operation of 3G-LTE and WCDMA.

· Hardware-accelerated features include FEC, FFT/DFT, MiMO MMSE (Minimum Mean Square Error), and MLD (Maximum Likelihood Decoder) flexible equalisers, as well as matrix inversion made possible by floating-point arithmetic and IRC (Interference Rejection Combining) receivers.

· The MSC8157 incorporates a high speed DDR interface, ample internal memory, CPRI (Common Public Radio Interface) 6G antenna interfaces and two Serial-RapidIO Gen 2, enabling 5G per lane with sophisticated messaging capability.

· The MSC8157 and MSC8158 DSPs include advanced WCDMA Chiprate acceleration, eliminating OEMs’ need to develop their own ASIC or FPGA. The high throughput and flexible Chiprate acceleration with capacity of up to 512 physical channels allows OEMs to deploy their own variant of Chiprate algorithms.

Development support

Freescale helps OEMs achieve fast time to market with its CodeWarrior suite of development tools embedded with highly optimising compiler technology, the MSC8157ADS evaluation board, and fully optimised software kernels for 3G-LTE and WCDMA.