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The DRAO Synthesis Telescope (ST) is a forefront telescope for imaging large-scale neutral hydrogen and polarized radio continuum emission at arcminute resolution. Equipped for observations at 1420 and 408 MHz, the ST completed the Canadian Galactic Plane Survey, providing pioneering measurements of arcminute-scale structure in HI emission and self-absorption and of the diffuse polarized emission, using a fine grid of Rotation Measures to chart the large-scale Galactic magnetic field, and advancing the knowledge of the Galactic rotation curve. In this paper we describe a plan for renewal of the Synthesis Telescope that will create a forefront scientific instrument, a testbed for new radio astronomy technologies, and a training ground for the next generation of Canadian radio astronomers and radio telescope engineers. The renewed telescope will operate across the entire range 400 to 1800 MHz. Collaborations between DRAO and university partners have already demonstrated a novel feed antenna to cover this range, low-noise amplifiers, and a new GPU-based correlator of bandwidth 400 MHz. The renewed ST will provide excellent sensitivity to extended HI, covering the Galactic disk and halo, spectro-polarimetry with unprecedented resolution in angle and in Faraday depth, the ability to search for OH masers in all four 18-cm lines simultaneously, and sensitive recombination-line observations stacked over as many as forty transitions. As a testbed the renewed ST will evaluate low-cost digital clocking and sampling techniques of wide significance for the ngVLA, SKA, and other future telescopes, and a prototype of the digital correlator developed at DRAO for SKA-mid., Comment: A White Paper submitted to the Long Range Plan 2020 for Canadian astronomy

This paper will give an overview of the unique mechanical and optical design of the DVA-1 telescope. The rim supported carbon fibre reflector surfaces are designed to be both low cost and have high performance under wind, gravity, and thermal loads. The shaped offset Gregorian optics offer low and stable side lobes along with a large area at the secondary focus for multiple feeds with no aperture blockage. Telescope performance under ideal conditions as well as performance under gravity, wind, and thermal loads will be compared directly using calculated radiation patterns for each of these operating conditions.