A method of receiving a plurality of data streams at an electromagnetic field receiver in a wireless telecommunications network, wherein the electromagnetic field receiver comprises a first optical transmitter, a second optical transmitter (225a, 225b), a first transmission medium, a second transmission medium, a first photodetector and a second photodetector, the first and second transmission media being spatially distinct, wherein the first optical transmitter is configured to transmit a first probe signal to the first photodetector through the first transmission medium at a first probe frequency and further configured to transmit a second probe signal to the second photodetector through the second transmission medium at a second probe frequency, and the second optical transmitter (225a, 225b) is configured to transmit a first coupling signal through the first transmission medium at a first coupling frequency and further configured to transmit a second coupling signal through the second transmission medium at a second coupling frequency, wherein the first probe frequency and first coupling frequency are set to excite electrons of the first transmission medium to a first predetermined Rydberg state so as to induce an Electromagnetic Induced Transparency, EIT, effect in the first transmission medium such that an incident electromagnetic field at a first frequency at the first transmission medium causes a detectable change in the first probe signal at the first photodetector, wherein the second probe frequency and second coupling frequency are set to excite electrons of the second transmission medium to a second predetermined Rydberg state so as to induce an EIT effect in the second transmission medium such that an electromagnetic field at a second frequency incident at the second transmission medium causes a detectable change in the second probe signal at the second photodetector, wherein the plurality of data streams are time multiplexed in a first time frame comprising a plurality of timeslots, such that a first data stream is communicated in a first subset of the plurality of timeslots of the first time frame and a second data stream is communicated in a second subset of the plurality of timeslots of the first time frame, the method comprising the steps of: obtaining data indicating detection by the first photodetector, in the first probe signal, of a first electromagnetic field incident at the first transmission medium during a timeslot of the first subset of the plurality of timeslots; associating the detected first electromagnetic field with a first data stream of the plurality of data streams; obtaining data indicating detection by the second photodetector, in the second probe signal, of a second electromagnetic field incident at the second transmission medium during a timeslot of the second subset of the plurality of timeslots; and associating the detected second electromagnetic field with a second data stream of the plurality of data streams. obtaining data indicating detection by the first photodetector, in the first probe signal, of a first electromagnetic field incident at the first transmission medium during a timeslot of the first subset of the plurality of timeslots; associating the detected first electromagnetic field with a first data stream of the plurality of data streams; obtaining data indicating detection by the second photodetector, in the second probe signal, of a second electromagnetic field incident at the second transmission medium during a timeslot of the second subset of the plurality of timeslots; and associating the detected second electromagnetic field with a second data stream of the plurality of data streams.