A system comprising: an implantable neural stimulator (114, 1500) comprising one or more electrodes, at least one antenna (1505, 1525) free of an inductive coil and an electrode interface; and an external radio-frequency pulse generator module comprising: an antenna module configured to: send one or more input signals to the at least one antenna in the implantable neural stimulator through non-inductive electrical radiative coupling, the one or more input signals containing electrical energy and polarity assignment information that designates polarity assignments of the one or more electrodes of the implantable neural stimulator, wherein the implantable neural stimulator is configured to: control the electrode interface such that the one or more electrodes have the polarities designated by the polarity assignment information, create one or more electrical pulses suitable for stimulation of neural tissue using the electrical energy contained in the one or more input signals that are received from the external RF pulse generator module through the non-inductive electrical radiative coupling, and supply the one or more electrical pulses to the one or more electrodes through the electrode interface such that the one or more electrodes apply the one or more electrical pulses to neural tissue with the polarities designated by the polarity assignment information. an implantable neural stimulator (114, 1500) comprising one or more electrodes, at least one antenna (1505, 1525) free of an inductive coil and an electrode interface; and an external radio-frequency pulse generator module comprising: an antenna module configured to: send one or more input signals to the at least one antenna in the implantable neural stimulator through non-inductive electrical radiative coupling, the one or more input signals containing electrical energy and polarity assignment information that designates polarity assignments of the one or more electrodes of the implantable neural stimulator, wherein the implantable neural stimulator is configured to: control the electrode interface such that the one or more electrodes have the polarities designated by the polarity assignment information, create one or more electrical pulses suitable for stimulation of neural tissue using the electrical energy contained in the one or more input signals that are received from the external RF pulse generator module through the non-inductive electrical radiative coupling, and supply the one or more electrical pulses to the one or more electrodes through the electrode interface such that the one or more electrodes apply the one or more electrical pulses to neural tissue with the polarities designated by the polarity assignment information. control the electrode interface such that the one or more electrodes have the polarities designated by the polarity assignment information, create one or more electrical pulses suitable for stimulation of neural tissue using the electrical energy contained in the one or more input signals that are received from the external RF pulse generator module through the non-inductive electrical radiative coupling, and supply the one or more electrical pulses to the one or more electrodes through the electrode interface such that the one or more electrodes apply the one or more electrical pulses to neural tissue with the polarities designated by the polarity assignment information.