The use of small satellites has opened up new areas of opportunity enabling the use of this technology to solve problems
with a high level of confidence at low cost for many areas including the remote sensing area. This paper presents the
technical considerations for the design of a multispectral optical imaging system suitable for medium-resolution image
acquisition working under the limitations of a small satellite, specifically a nano-satellite (satellite of less than 10Kg).
The specifications of this kind of satellite platforms and how this affects the design considerations are discussed. The
document describes a proposed design for the system and the applicability and potential use of such development.
The SATEX I project, is a Mexican effort with the purpose of design, construct and operate an experimental microsatellite in low-earth orbit, in a university and multi-institutional environment. The scientific mission is focused on electronic telecommunications research with a Ka band experiment and the optical payload; also, a CCD camera is included for remote image acquisition. The SATEX Optical Payload (SOP) is an experimental system aimed to perform BER and attenuation measurements. The SOP consists in a laser transmitter in the 830 nm and a quad-photo receiver in the 530 nm. The experiment is divided in two features: the downlink where the measurements will be performed and the uplink that will be used to perform the pointing of the experiment. The SOP has a control system to establish and keep a link by opto-electro-mechanical means, which tracks and acquires the optical beacon. This beacon is a non-modulated light source generated by the earth station. When the satellite receives it, it is then used to acknowledge the location of the earth station; therefore, the modulated laser beam can be transmitted to Earth. The technical looks of design of all the subsystems and the prototype obtained are presented and the link calculation is discussed.