The tests on the laboratory have been carried out using two different equipment sets. A first phase of testing was carried out in 2014 at the University of the Basque Country using a prototype transmission-reception system based on Software Defined Radio. The second set of measurements were carried out during 2014 and 2015 at the ETRI, using the first hardware prototype of LDM (see HW Prototype).
The lab set-up at the University of the Basque Country was based on Vector Signal Generators and analyzers as the digital to analogue and analogue to digital converting modules.
The objective of this round of testing was to evaluate the implementation loss associated to ADC/DAC, synch impairments, real channel estimation, etc. The following figures provide some result examples.
The results are in line with the expectations for a first generation receiver. It is remarkable that the difference between simulations and lab implementation for mobile worst case is lower than 2 dB.