Extending REACH: A Scalable Backend for Multi-Receiver 21cm Observations

The Radio Experiment for the Analysis of Cosmic Hydrogen (REACH) [1] is a pioneering instrument that aims to detect the 21cm global signal from the early Universe.We propose an extension to REACH that supports multiple receivers while maintaining a common backend.This enhancement aims to improve the ability to mitigate systematic effects in 21cm cosmology observations.The current REACH system employs a single-receiver configuration with a single dipole antenna.Our proposed extension introduces support for multiple receivers, each dedicated to a single antenna, while preserving the existing digital backend architecture.Each receiver in the extended REACH system is described through configuration files using the YAML format.This approach allows for flexible and easily maintainable receiver setups.Similarly, all hardware components are described using YAML files, with each individual component assigned a unique ID.This ID system enables differentiation between identical devices in different receivers connected to the server, ensuring precise control and monitoring of the entire system.