A Domain-Specific Language for Software-Defined Radio

Abstract

Software-defined radio (SDR) is a demanding domain; real-world wireless protocols require high data rates and low latency. Existing SDR platforms, typically based on FPGAs, provide the necessary substrate for meeting these requirements, but the high-level tools available to program them are not capable of fully exploiting the underlying hardware to meet rigorous performance requirements. Ziria [11] demonstrated that a high-level language can compete in this demanding space, but its design was ad-hoc and overly influenced by the needs of the compiler writer since its surface language does double duty as the compiler’s intermediate language.

We present a re-formulation of Ziria’s surface language that includes a new type system that allows this language, which is effectful, to elaborate into a pure, monadic language where effects such as input/output and reference manipulation can be distinguished purely by type. This re-formulation and its elaboration into a core language is embodied in a new compiler for Ziria, kzc. By choosing an appropriate type system, awkward syntactic distinctions currently made by Ziria can be eliminated, although our new implementation maintains source compatibility with the original compiler due to a large body of existing Ziria code (a full 802.11 physical layer implementation). Our contribution is a description of the surface language, its type system, and its elaboration into a core language. We also show that far from being limited to the SDR domain, the constructs built-in to Ziria are applicable to other resource-constrained domains that require high-speed data processing.