An electromagnetic measurement system to test a device under test, DUT, the system comprising: a plurality of nodes, each node within an anechoic chamber in proximity to and in communication with a different antenna of an array of antennas distributed at various angles around the DUT, each node including a combination of: a transceiver in close proximity to an antenna; a channel emulator in proximity to and in communication with an antenna via the transceiver; and a communication tester (68, CT) in proximity to and in communication with the channel emulator, the communication tester configured, if operating in an outgoing mode, to generate a digital outgoing communication signal to be impaired by the channel emulator and the communication tester configured, if operating in an incoming mode, to receive an incoming communication signal impaired by the channel emulator; and the channel emulator configured to emulate a channel by impairing the digital outgoing communication signal if operating in the outgoing mode and impairing an incoming digital communication signal if operating in the incoming mode to produce an impaired communication signal; and a controller to provide control signals to each communication tester, the control signals being configured to synchronize the communication testers in time and content; and if operating in the outgoing mode, the plurality of communication testers in the plurality of nodes being configured to generate a set of outgoing signals that are synchronized in content so that by impairing each such synchronized outgoing signal by a different impairment, a spatial channel having multiple different paths affecting a signal radiated from a source of the content is emulated. a plurality of nodes, each node within an anechoic chamber in proximity to and in communication with a different antenna of an array of antennas distributed at various angles around the DUT, each node including a combination of: a transceiver in close proximity to an antenna; a channel emulator in proximity to and in communication with an antenna via the transceiver; and a communication tester (68, CT) in proximity to and in communication with the channel emulator, the communication tester configured, if operating in an outgoing mode, to generate a digital outgoing communication signal to be impaired by the channel emulator and the communication tester configured, if operating in an incoming mode, to receive an incoming communication signal impaired by the channel emulator; and the channel emulator configured to emulate a channel by impairing the digital outgoing communication signal if operating in the outgoing mode and impairing an incoming digital communication signal if operating in the incoming mode to produce an impaired communication signal; and a transceiver in close proximity to an antenna; a channel emulator in proximity to and in communication with an antenna via the transceiver; and a communication tester (68, CT) in proximity to and in communication with the channel emulator, the communication tester configured, if operating in an outgoing mode, to generate a digital outgoing communication signal to be impaired by the channel emulator and the communication tester configured, if operating in an incoming mode, to receive an incoming communication signal impaired by the channel emulator; and the channel emulator configured to emulate a channel by impairing the digital outgoing communication signal if operating in the outgoing mode and impairing an incoming digital communication signal if operating in the incoming mode to produce an impaired communication signal; and a controller to provide control signals to each communication tester, the control signals being configured to synchronize the communication testers in time and content; and if operating in the outgoing mode, the plurality of communication testers in the plurality of nodes being configured to generate a set of outgoing signals that are synchronized in content so that by impairing each such synchronized outgoing signal by a different impairment, a spatial channel having multiple different paths affecting a signal radiated from a source of the content is emulated.