One disclosure of the present specification proposes a method for receiving a Narrowband Reference Signal (NRS) by a Narrow band Internet of Things (NB-IoT) device. The method may comprise receiving the NRS on at least one or more orthogonal frequency division multiplexing (OFDM) symbols. The one or more OFDM symbols are in a time division duplex (TDD) subframe. If the TDD subframe corresponds to a TDD special subframe, the one or more OFDM symbols for receiving the NRS is determined based on which TDD special subframe configuration index among a plurality of TDD special configuration indexes is used by the TDD special subframe.

One disclosure of the present specification proposes a method for receiving a Narrowband Reference Signal (NRS) by a Narrow band Internet of Things (NB-IoT) device. The method may comprise receiving the NRS on at least one or more orthogonal frequency division multiplexing (OFDM) symbols. The one or more OFDM symbols are in a time division duplex (TDD) subframe. If the TDD subframe corresponds to a TDD special subframe, the one or more OFDM symbols for receiving the NRS is determined based on which TDD special subframe configuration index among a plurality of TDD special configuration indexes is used by the TDD special subframe.

This specification discloses a method for transmitting a demodulation reference signal (DMRS) in a wireless communication system supporting NB (Narrow-Band)-IoT (Internet of Things), the method performed by a User Equipment (UE) including generating a reference signal sequence used for demodulation; mapping the reference signal sequence to at least one symbol; and transmitting the demodulation reference signal (DMRS) to a base station through a single subcarrier in the at least one symbol.

This specification discloses a method for transmitting a demodulation reference signal (DMRS) in a wireless communication system supporting NB (Narrow-Band)-IoT (Internet of Things), the method performed by a User Equipment (UE) including generating a reference signal sequence used for demodulation; mapping the reference signal sequence to at least one symbol; and transmitting the demodulation reference signal (DMRS) to a base station through a single subcarrier in the at least one symbol.

A communication module for a building technology device, especially a luminaire, is provided, wherein the communication module is configured to be connectable to an IoT-network and a communication bus, and being configured for a bi-directional communication on the IoT-network and the communication bus, wherein the communication module is configured to convert communication data between the communication bus and the IoT-network.

One disclosure of the present specification proposes a method for receiving a Narrowband Reference Signal (NRS) by a Narrow band Internet of Things (NB-IoT) device. The method may comprise receiving the NRS on at least one or more orthogonal frequency division multiplexing (OFDM) symbols. The one or more OFDM symbols are in a time division duplex (TDD) subframe. If the TDD subframe corresponds to a TDD special subframe, the one or more OFDM symbols for receiving the NRS is determined based on which TDD special subframe configuration index among a plurality of TDD special configuration indexes is used by the TDD special subframe.

This specification discloses a method for transmitting a demodulation reference signal (DMRS) in a wireless communication system supporting NB (Narrow-Band)-IoT (Internet of Things), the method performed by a User Equipment (UE) including generating a reference signal sequence used for demodulation; mapping the reference signal sequence to at least one symbol; and transmitting the demodulation reference signal (DMRS) to a base station through a single subcarrier in the at least one symbol.

One disclosure of the present specification proposes a method for receiving a Narrowband Reference Signal (NRS) by a Narrow band Internet of Things (NB-IoT) device. The method may comprise receiving the NRS on at least one or more orthogonal frequency division multiplexing (OFDM) symbols. The one or more OFDM symbols are in a time division duplex (TDD) subframe. If the TDD subframe corresponds to a TDD special subframe, the one or more OFDM symbols for receiving the NRS is determined based on which TDD special subframe configuration index among a plurality of TDD special configuration indexes is used by the TDD special subframe.

One disclosure of the present specification proposes a method for receiving a Narrowband Reference Signal (NRS) by a Narrow band Internet of Things (NB-IoT) device. The method may comprise receiving the NRS on at least one or more orthogonal frequency division multiplexing (OFDM) symbols. The one or more OFDM symbols are in a time division duplex (TDD) subframe. If the TDD subframe corresponds to a TDD special subframe, the one or more OFDM symbols for receiving the NRS is determined based on which TDD special subframe configuration index among a plurality of TDD special configuration indexes is used by the TDD special subframe.

This specification discloses a method for transmitting a demodulation reference signal (DMRS) in a wireless communication system supporting NB (Narrow-Band)-IoT (Internet of Things), the method performed by a User Equipment (UE) including generating a reference signal sequence used for demodulation; mapping the reference signal sequence to at least one symbol; and transmitting the demodulation reference signal (DMRS) to a base station through a single subcarrier in the at least one symbol.