An expurgated pulse position modulation (EPPM) technique can be used to encode information for wireless transmission. Such an EPPM technique can be compatible with a simple receiver architecture, such as including a shift register and pulse position modulation (PPM) decoder. A multi-level EPPM (MEPPM) approach can increase the available symbols in the modulation constellation and can be used to accommodate multiple users or devices concurrently. Interleaving techniques can be used such as to reduce inter-symbol interference. An optical transmitter and an optical receiver can be used, such as including using energy in a visible range of frequencies. In an example, an optical source such as including one or more light emitting diodes can provide visible light for illumination, and the EPPM technique can include using codewords specified to provide a desired dimming level when such codewords are used to intensity modulate the optical source, without perceptible flicker.

In a detection circuit, inputs correspond to received indications of vector signaling code words received by a first integrated circuit from a second integrated circuit. With four inputs, the circuit compares a first pair to obtain a first difference result and compares a second pair, disjoint from the first pair, to obtain a second difference result. The first and second difference results are then summed to form an output function. A system might use a plurality of such detection circuits to arrive at an input word. The circuit can include amplification, equalization, and input selection with efficient code word detection. The vector signaling code can be a Hadamard matrix code encoding for three input bits. The circuit might also have frequency-dependent gain, a selection function that directs one of the summation function result or the first difference result to the output function, variable gain, and/or a slicer.

A data receiving circuit includes a decision feedback equalization circuit, configured to perform decision feedback equalization on a receive circuit based on a feedback signal to adjust a first output signal and a second output signal, where the feedback signal is obtained based on previously received data, the decision feedback equalization circuit responds to a first control signal group and a second control signal group to change an adjustment capability, the first control signal group corresponds to one data port corresponding to a data signal, and the second control signal group corresponds to all data ports. The capability of the decision feedback equalization circuit can be controlled to adjust the first output signal and the second output signal, where the adjustment capability has a wide adjustable range, to reduce impact of intersymbol interference of received data on the data receiving circuit.

Radio network nodes, wireless devices, and related methods are provided in which a pseudo-random sequence initialization value, which is used during the generation of pseudo-random and/or scrambling sequences, is based, at least in part, on a first identifier, wherein the first identifier is equal to a first parameter if the first parameter has been configured and if a second identifier corresponds to a wireless-device-specific identifier.

Radio network nodes, wireless devices, and related methods are provided in which a pseudo-random sequence initialization value, which is used during the generation of pseudo-random and/or scrambling sequences, is based, at least in part, on a first identifier, wherein the first identifier is equal to a first parameter if the first parameter has been configured and if a second identifier corresponds to a wireless-device-specific identifier.