ICE: a scalable, low-cost FPGA-based telescope signal processing and networking system

K. Bandura; A. N. Bender; J. F. Cliche; T. de Haan; M. A. Dobbs; A. J. Gilbert; S. Griffin; G. Hsyu; D. Ittah; J. Mena Parra; J. Montgomery; T. Pinsonneault-Marotte; S. Siegel; G. Smecher; Q. Y. Tang; K. Vanderlinde; N. Whitehorn

arXiv · 1608.06262

ICE: a scalable, low-cost FPGA-based telescope signal processing and networking system

K. Bandura·A. N. Bender·J. F. Cliche·T. de Haan·M. A. Dobbs·A. J. Gilbert·S. Griffin·G. Hsyu·D. Ittah·J. Mena Parra·J. Montgomery·T. Pinsonneault-Marotte·S. Siegel·G. Smecher·Q. Y. Tang·K. Vanderlinde·N. Whitehorn

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Abstract

We present an overview of the 'ICE' hardware and software framework that implements large arrays of interconnected FPGA-based data acquisition, signal processing and networking nodes economically. The system was conceived for application to radio, millimeter and sub-millimeter telescope readout systems that have requirements beyond typical off-the-shelf processing systems, such as careful control of interference signals produced by the digital electronics, and clocking of all elements in the system from a single precise observatory-derived oscillator. A new generation of telescopes operating at these frequency bands and designed with a vastly increased emphasis on digital signal processing to support their detector multiplexing technology or high-bandwidth correlators---data rates exceeding a terabyte per second---are becoming common. The ICE system is built around a custom FPGA motherboard that makes use of an Xilinx Kintex-7 FPGA and ARM-based co-processor. The system is specialized for specific applications through software, firmware, and custom mezzanine daughter boards that interface to the FPGA through the industry-standard FMC specifications. For high density applications, the motherboards are packaged in 16-slot crates with ICE backplanes that implement a low-cost passive full-mesh network between the motherboards in a crate, allow high bandwidth interconnection between crates, and enable data offload to a computer cluster. A Python-based control software library automatically detects and operates the hardware in the array. Examples of specific telescope applications of the ICE framework are presented, namely the frequency-multiplexed bolometer readout systems used for the SPT and Simons Array and the digitizer, F-engine, and networking engine for the CHIME and HIRAX radio interferometers.

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K. Bandura, A. N. Bender, J. F. Cliche, T. de Haan, M. A. Dobbs, A. J. Gilbert, S. Griffin, G. Hsyu, D. Ittah, J. Mena Parra, J. Montgomery, T. Pinsonneault-Marotte, S. Siegel, G. Smecher, Q. Y. Tang, K. Vanderlinde, N. Whitehorn. 2016-08-22. ICE: a scalable, low-cost FPGA-based telescope signal processing and networking system. https://arxiv.org/abs/1608.06262

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