sophisticated parameter estimation method like the Markov chain Monte Carlo (MCMC) to extract the relevant information. However, before getting involved in the complexities of the parameter estimation methods, one needs to set up appropriate observational strategies to detect the signal. Detection of the signal from the cosmic dawn is itself very challenging as it is very weak compared to the system noise and the astrophysical foregrounds. In general, one has to integrate the signal over a large observing time to reduce the noise and also use some efficient foreground subtraction method to recover the signal given that the foregrounds are 4-5 orders of magnitude stronger. In this paper, we explore, in detail, the detection of the early sources during the cosmic dawn in [H [i ]{}]{} 21-cm images in the presence of system noise and the foregrounds. Our analysis is based on realistic simulations of the signal, system noise, and the relevant astrophysical foregrounds, followed by predictions related to the detectability of the early sources using the SKA1-low. These predictions would be quite useful to plan for observational strategies for detecting the sources in 21-cm observations.

The paper is organized in the following way. In section \[simu\], we describe the 