###### Abstract
There is also a general need for increasing automatic cloud observations for climate studies at monitoring laboratories located in the coastal range of Chile, where the understanding of fog and low clouds behavior remains a relevant challenge. Although the performance of current commercial radars is adequate, the size, power consumption, and cost of them inhibit its use to study the fog dynamics in the mesoscale or as network instruments. The use of frequency-modulated continuous-wave (FMCW) radar has significantly reduced the cost of the system with a low impact on performance [12]. However, current commercial FMCW radars are still large in size, require hundreds of watts in power, and cost hundreds of thousands of dollars, which is still a restrictive solution to cover the large areas of the Chilean coastal range. For this  
Figure 1: Example of a cloud intersecting with the Chilean coastal range in _Lo Prado_ tunnel, west from Santiago, Chile’s capital. (**a**) shows the east side of the tunnel. It is possible to see a clear sky at that side of the range; (**b**) shows a close up to the top of the mountain over the tunnel, where the cloud is appearing; (**c**) presents the situation at the west side of the tunnel, where there is a cloudy sky. Images were taken on 11 November 2019, in trip from Santiago to Valparaiso, before and after crossing the tunnel. reason, taking advantage of the Chilean topography, we proposed a miniaturized FMCW radar much cheaper than pulsed radars and lower in cost compared to current cloud commercial FMCW radars [13]. Although for this work we used recycled radio astronomy components, these components are nowadays available commercially for satellite communication. The current cost of our proposed radar is less than 20,000 US dollars. The reduction in size and power consumption is also key to facilitate the location and maintenance of the instruments at isolated locations in the coastal range. These features offer the possibility of using a larger number of instruments, allowing multi-point measurements. In our first attempt of the compact radar, the range resolution was larger than the range allowing just a pixel in the measurement [13]. In this article, we present the changes to the first radar prototype to improve the height estimation of the cloud base, which allows for a better characterization of clouds within the boundary layer. In addition, we present a novel procedure for distance calibration by using a drone. By using this procedure together with an internal calibration of the radar, we conclude that the new version of our system possesses a range coverage over 500 m with a range resolution of \(\sim\)20 m. Finally, we present the results of a field campaign, where simultaneous measurements of a cloud are taken with the radar in and a commercial ceilometer. In addition, we present MODIS data of the area together with radiosonde data. The sounding was launched from Santo Domingo, about 120 km south from our field campaign, about two hours before of our Radar and Lidar measurements. This type of radar not only can operate alone but might complement commercial ceilometer. In [14], it was shown that FMCW radar measuring simultaneously with a ceilometer provides multiple advantages. The combination of both ceilometer and FMCW cloud radar can provide the boundaries of a cloud layer in a cost effective manner during continuous operational use in a coastal cloud laboratory taking advantage of the proximity of clouds.