## 1 Introduction
### Dattaking Campaigns  
The first commissioning tests were carried out in 2018-2020 at the UAB Campus. After turning off internal street lighting, the area was sufficiently dark on those nights when the pBRL was tested. During that time, the system was gradually commissioned, complemented with LOTR and control hardware and software. In 2020, the primary mirror, degraded by being inoperative since the time when CLUE was operating (until the year 2000), was realuminized and quartz-coated [16]. Only one data set, taken on 7 December 2020, was obtained at the UAB Campus after this intervention. Shortly after,  
Figure 1: A schematic drawing of the pBRL and its main components: the receiver, comprising the telescope, the polychromator, and the data acquisition unit, and the transmitter, comprising the laser and guiding mirrors. The figure has been adopted from Ballester et al. [16].  
Figure 2: Pictures of the pBRL during its test campaign at the ORM next to CTAO’s first Large Size Telescope (LST-1). On the left side, a close-up of the LIDAR is shown with closed mirror protection petals. The LST-1 telescope is seen in the background. On the right side, the protective enclosure container is visible, as well as the full area within the LST-1, which had been temporarily lent to the pBRL.  
the pBRL was shipped to the ORM, the CTAO-N site. It was temporarily installed next to the Large Size Telescope (LST)-1, the first installation of CTAO-N (see Figure 2) near its final future location.  
The pBRL was deployed at ORM from February 2021 to May 2022. During this period, the pBRL operated for a total of 33 twilight time slots during moon nights and accumulated approximately 20 h of data. Its operation was, due to restrictions imposed by the Instituto de Astrofisica de Canarias (IAC), which managed the ORM site, and the operation scheme of the LST-1 telescope, mainly confined to the astronomical twilight periods of moonlit nights, when the rest of the observatory, and particularly the LST-1, did not operate. This constraint, along with the need to protect the equipment, resulted in reduced LIDAR performance, as the system was designed to operate during dark nights or moderate moonlight when the CTAO would be collecting data. The eruption of the Cumbre Vieja (Tajogaite) volcano in September 2021 and the subsequent deposition of volcanic ash also led to a suspension of observatory activities, including pBRL testing. Operation resumed in January 2022 and lasted until May before the LIDAR was finally dismantled and transported back to the UAB Campus.  
The paper is structured as follows. In Section 2.1, we characterize the pBRL via the power budget simulation method, computing the expected return power and the signal-to-noise ratio and verifying the expectation to meet the CTAO requirements. In Sections 2.2-2.4, we describe in detail the signal reconstruction procedures that we have developed, with special consideration on statistical soundness. Section 2.5 presents the inversion methods used for the characterization of the ground layer and clouds. In Section 3, we show results on the performance of the pBRL using several case studies of data taken during measurement campaigns close to Barcelona and at the ORM, highlighting cases of clear sky, the presence of calima, and atmospheric volcanic ash. We discuss and compare our pBRL with other current systems in Section 4 and draw our conclusions in Section 5.