A system for measuring in an anonymous manner one or more spatial positions of one or more user devices within a region, wherein the system includes a wireless arrangement for receiving signals from the one or more user devices for determining the one or more spatial positions of the one or more user devices and a plurality of nodes which are spatially distributed at mutually different spatial positions within the region, wherein - the wireless arrangement is operable to receive one or more Media Access Control, MAC, codes from the one or more user devices , wherein the one or more MAC codes include N bits for each of the one or more user devices; and - the system is operable to apply a bitmask to mask the one or more MAC codes to form one or more corresponding secondary identification codes which decreases an entropy of the one or more MAC codes by K bits; and - the system is operable to hash the one or more corresponding secondary identification codes to increase an entropy of each of the one or more corresponding secondary identification codes by M bits to generate a post-ID code for each of the one or more user devices, wherein the post-ID code is stored for each of the one or more user devices for providing the one or more spatial positions for each of the one or more user devices; or - the system is operable to hash the one or more MAC codes to increase an entropy of the one or more MACcodes by M bits; and - the system is operable to apply a bitmask to mask the entropy-increased one or more MAC codes to form one or more corresponding secondary identification codes which decreases an entropy of each of the one or more MAC codes by K bits to generate a post-ID code for each of the one or more user devices, wherein the post-ID code is stored for each of the one or more user devices for providing the one or more spatial positions for each of the one or more user devices. - the wireless arrangement is operable to receive one or more Media Access Control, MAC, codes from the one or more user devices , wherein the one or more MAC codes include N bits for each of the one or more user devices; and - the system is operable to apply a bitmask to mask the one or more MAC codes to form one or more corresponding secondary identification codes which decreases an entropy of the one or more MAC codes by K bits; and - the system is operable to hash the one or more corresponding secondary identification codes to increase an entropy of each of the one or more corresponding secondary identification codes by M bits to generate a post-ID code for each of the one or more user devices, wherein the post-ID code is stored for each of the one or more user devices for providing the one or more spatial positions for each of the one or more user devices; or - the system is operable to hash the one or more MAC codes to increase an entropy of the one or more MACcodes by M bits; and - the system is operable to apply a bitmask to mask the entropy-increased one or more MAC codes to form one or more corresponding secondary identification codes which decreases an entropy of each of the one or more MAC codes by K bits to generate a post-ID code for each of the one or more user devices, wherein the post-ID code is stored for each of the one or more user devices for providing the one or more spatial positions for each of the one or more user devices. <EOS>