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The Simons Observatory (SO) is an upcoming cosmic microwave background(CMB) experiment located on Cerro Toco, Chile, that will map the microwave sky in temperature and polarization in six frequency bands spanning 27 to 285 GHz. SO will consist of one 6-meter Large Aperture Telescope (LAT) fielding∼30,000 detectors and an array of three 0.42-meter Small Aperture Telescopes (SATs) fielding an additional 30,000 detectors. This synergy will allow for the extremely sensitive characterization of the CMB over an-gular scales ranging from an arcmin to tens of degrees, enabling a wide range of scientific output. Here we focus on the SATs targeting degree angular scales with successive dichroic instruments observing at Mid-Frequency (MF: 93/145 GHz), Ultra-High-Frequency (UHF:225/285 GHz), and Low-Frequency (LF: 27/39 GHz). The three SATs will be able to map∼10% of the sky to a noise level of∼2 μK-arcmin when combining 93 and 145 GHz. The multiple frequency bands will allow the CMB to be separated from galactic foregrounds (primarily synchrotron and dust), with the primary science goal of characterizing the primordial tensor-to-scalar ratio, r, at a target level ofσ(r)≈0.003.

The Simons Observatory will measure the cosmic microwave background tempera-ture and polarization using a suite of new telescopes in the Atacama Desert in Chile. The Simons Observatory will use dichroic transition edge sensor (TES) bolometer arrays spanning six frequency bands from 27 to 280 GHz. The Simons Observa-tory will pioneer the use of a densely packed multiplexing architecture based on the microwave SQUID multiplexer ( 𝜇mux), housing ∼2000 microwave resonators, each coupled to a TES. The Simons Observatory aims to multiplex each array of ∼2000 detectors with a single pair of coaxial cables and requires a multiplexing factor of ∼1000 . The Simons Observatory cryogenic readout system is called the universal microwave multiplexing module (UMM). The UMM couples to both horn and lenslet-coupled detector arrays and is integrated into the universal focal-plane module (UFM) after being independently characterized. We present processes we have developed for highly repeatable and automated integration methods of UMMs, which will be needed for the production of the 49 UFMs required for the first stage of the Simons Observatory.