In an eleventh exemplary embodiment, the wireless communication includes transmission of a demodulation reference signal within the determined resource allocation.
In a twelfth exemplary embodiment, the determined resource allocation occurs at the same time as and overlaps in frequency with another resource allocation from the set allocated for wireless communication between other radio nodes, with each wireless communication including transmission of a demodulation reference signal.
In a thirteenth exemplary embodiment, the demodulation reference signals are formed from a cyclic shift of different base sequences.
In a fourteenth exemplary embodiment, the narrowband communication system is a narrowband Internet of Things system.
In a fifteenth exemplary embodiment, the narrowband communication system is deployed in-band or in a guard band of a Long Term Evolution system.