An integrated circuit comprising: a plurality of radio circuits , wherein each radio circuit includes: a radio circuit input configured to receive radio frequency, RF, signals from a respective receiver; a radio circuit output configured to output RF signals to a respective transmitter; a switching network for performing a built-in-self-test, BIST, procedure; and circuitry configured to control the switching network to perform said BIST procedure, wherein the switching network comprises: a plurality of combiners , each combiner having an input and an output ; a plurality of transmitter connection switches , wherein each transmitter connection switch is operable selectively to couple each radio circuit output to the input of each of said combiners; a combiner switch having an input and an output , wherein the input is coupled to the output of each combiner , wherein the combiner switch is operable selectively to output an output signal received from each of said combiners ; a splitter switch having an input and an output , wherein the input of the splitter switch is coupled to an output of the combiner switch via one or more further switches ; a plurality of splitters , each splitter having an input and an output , wherein the input of each splitter is coupled to the output of the splitter switch , wherein the splitter switch is operable selectively to output an output signal received from the one or more further switches to one of said splitters; characterised in that the integrated circuit further comprises a plurality of receiver connection switches , wherein each receiver connection switch is operable selectively to couple the output of each splitter to one of said radio circuit inputs. a plurality of radio circuits , wherein each radio circuit includes: a radio circuit input configured to receive radio frequency, RF, signals from a respective receiver; a radio circuit output configured to output RF signals to a respective transmitter; a radio circuit input configured to receive radio frequency, RF, signals from a respective receiver; a radio circuit output configured to output RF signals to a respective transmitter; a switching network for performing a built-in-self-test, BIST, procedure; and circuitry configured to control the switching network to perform said BIST procedure, a plurality of combiners , each combiner having an input and an output ; a plurality of transmitter connection switches , wherein each transmitter connection switch is operable selectively to couple each radio circuit output to the input of each of said combiners; a combiner switch having an input and an output , wherein the input is coupled to the output of each combiner , wherein the combiner switch is operable selectively to output an output signal received from each of said combiners ; a splitter switch having an input and an output , wherein the input of the splitter switch is coupled to an output of the combiner switch via one or more further switches ; a plurality of splitters , each splitter having an input and an output , wherein the input of each splitter is coupled to the output of the splitter switch , wherein the splitter switch is operable selectively to output an output signal received from the one or more further switches to one of said splitters; characterised in that the integrated circuit further comprises a plurality of receiver connection switches , wherein each receiver connection switch is operable selectively to couple the output of each splitter to one of said radio circuit inputs. <EOS>