Analysis
Imec and Target present innovative flexible forward error-correction solution for software-defined radios
Today imec and Target Compiler Technologies present a C-programmable flexible FEC (forward error correction) solution fit for future cellular, connectivity and broadcasting standards. This so-called “flex FEC” solution competes in area and throughput with dedicated fixed-function hardwired implementations, yet offers the flexibility to support multiple standards thanks to software programmability. The C-programmable flex FEC ASIP (application-specific instruction-set processor) template supports LDPC (low-density parity check), Turbo and Viterbi decoding. Imec designed and optimized the ASIP architecture and generated a matching software development kit, using IP Designer, Target’s tool-suite for ASIP design.
Imec’s ASIP architecture template can be instantiated for different standards to perform channel decoding. Various algorithmic-architectural co-optimizations enabled parallelization of the algorithms to meet the high throughput and latency requirements in a flexible processor. The solution meets throughput and latency specifications ranging from connectivity (WLAN 802.11n, 802.11ac) to broadcasting (DVB-T2/S2, CMMB, DVB-SH) and cellular standards (3GPP-LTE, 802.16e).
Target Compiler Technologies’ IP Designer tool-suite enabled the design-time architectural exploration and optimization of imec’s flex FEC solution and allowed a quick validation of the impact of architectural changes on throughput, latency, silicon area and power consumption. IP Designer automatically generated an optimizing C-compiler to compile the multi-standard FEC algorithms on the specialized FEC architecture exploiting the available instruction-level parallelism, and an instruction-set simulator to validate and profile the code running on the architecture.
The flex FEC template was instantiated for WLAN, WiMAX, 3GPP-LTE and DVB-S2/T2. A low-power register-transfer level hardware implementation of the core was automatically generated with the IP Designer tools, which resulted in a total core area and throughput competitive with state-of-the-art dedicated fixed-function hardwired solutions. The generic template, supporting both turbo and LDPC decoding can be pruned aggressively in case of LDPC decoding only, leading to substantial additional savings in area and power consumption.
Gert Goossens, Target’s CEO, said: “We are delighted with the ASIP implementation achievements of imec’s green radio program based on our IP Designer tools. This flex FEC template proves that programmable ASIP solutions can compete with fixed-function hardwired IP blocks in performance and area, for advanced wireless standards. In general, ASIP implementations reduce the design risk, can resolve issues with early non-frozen standards and enable SoC customers to include proprietary features in their chipsets. In recent years, IP Designer has been adopted by major industrial players to design their wireless modem solutions. Imec’s new flex FEC solution underscores the potential of ASIPs and of our tools also for next-generation wireless systems.”