In one arrangement, a system includes a light source to provide outgoing light having at least one time-varying attribute at a selected one of multiple wavelength channels, the at least one time-varying attribute including either/both of (a) a time-varying intensity profile and (b) a time-varying frequency deviation, a beam director to spatially direct the outgoing light into one of multiple directions in two dimensions into an environment having a spatial profile, the one of the multiple directions corresponding to the selected wavelength channel, a light receiver to receive at least part of the outgoing light reflected by the environment, and a processing unit to determine at least one characteristic associated with the at least one time-varying attribute of the reflected light at the selected one of the multiple wavelengths for estimation of the spatial profile of the environment associated with the corresponding one of the multiple directions.