Airfield multilateration system for detecting airfield traffic, comprising a plurality of airfield surveillance units , each of the plurality of airfield surveillance units comprising: a power supply module , a first radio antenna configured to receive an aircraft transponder signal, a receiver module coupled to the power supply module and configured to be coupled to the first radio antenna and comprising a first data communication port , wherein the receiver module is operable to convert the aircraft transponder signal received by the first radio antenna for transmission via the first data communication port, wherein the converted aircraft transponder signal allows for determining a position of a corresponding aircraft via multilateration, characterised in that each of the plurality of airfield surveillance units further comprises: a second radio antenna configured to receive and transmit 5G radio signals, and a 5G communication module coupled to the power supply module and configured to be coupled to the second radio antenna and operable to process 5G radio signals received or transmitted by the second radio antenna, wherein the 5G communication module and the second radio antenna are configured to operate as a transceiver for a private 5G cellular network, wherein the airfield multilateration system further comprises a central processing unit operable for data communication with the plurality of airfield surveillance units , the central processing unit comprising a computing module operable to determine an aircraft position based on the aircraft transponder signal received by multiple ones of the plurality of airfield surveillance units, wherein the 5G communication modules of the plurality of airfield surveillance units are configured to form a private 5G cellular network. a power supply module , a first radio antenna configured to receive an aircraft transponder signal, a receiver module coupled to the power supply module and configured to be coupled to the first radio antenna and comprising a first data communication port , wherein the receiver module is operable to convert the aircraft transponder signal received by the first radio antenna for transmission via the first data communication port, wherein the converted aircraft transponder signal allows for determining a position of a corresponding aircraft via multilateration, a second radio antenna configured to receive and transmit 5G radio signals, and a 5G communication module coupled to the power supply module and configured to be coupled to the second radio antenna and operable to process 5G radio signals received or transmitted by the second radio antenna, wherein the 5G communication module and the second radio antenna are configured to operate as a transceiver for a private 5G cellular network, wherein the airfield multilateration system further comprises a central processing unit operable for data communication with the plurality of airfield surveillance units , the central processing unit comprising a computing module operable to determine an aircraft position based on the aircraft transponder signal received by multiple ones of the plurality of airfield surveillance units, wherein the 5G communication modules of the plurality of airfield surveillance units are configured to form a private 5G cellular network. <EOS>