Improving the Spectral Efficiency of Modulation on Conjugate-Reciprocal Zeros (MOCZ) for Non-Coherent Short Packet Communications
Date
2023-01-11
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
0000-0003-1745-0799
Type
Thesis
Degree Level
Masters
Abstract
Future internet of things (IoT) applications need to meet the stringent requirements of ultra high reliability and ultra low-latency. To meet the ultra low-latency requirements, the IoT networks will be employing the short data packets for data transmission between the devices. Employing the short data packet communications (SPCs) is not straightforward as there are several design problems related to the SPCs which still remain unsolved.
Since the block length for SPCs is finite; the channel estimation is a challenging problem. This is because the conventionally used known pilot symbols to estimate the channel will severely degrade the spectral efficiency of SPCs. Recently a novel non-coherent modulation technique named as modulation on conjugate reciprocal zeros (MOCZ) was proposed which supports the blind detection of transmitted data, i.e., detection without the knowledge of channel. It is also well known that SPCs suffers from data rate loss as compared to the channel capacity limit. Hence, in this thesis, we aim to increase the spectral efficiency of MOCZ.
We improve the spectral efficiency of MOCZ by proposing a technique named as spectrally efficient modulation on conjugate reciprocal zeros (SE-MOCZ) which combines MOCZ with a technique named as faster than Nyquist (FTN) Signaling. Hence; in SE-MOCZ, we end up transmitting the coefficients of MOCZ, modulated on T-orthogonal pulses, at a rate faster than the Nyquist limit, i.e., τT, instead of T, where 0 < τ < 1. That said, we intentionally introduce inter symbol interference (ISI) between the received samples of SE MOCZ. To partially remove the ISI, we introduce a discrete-time filter at the receiver. We further optimize the radius of complex zeros of SE-MOCZ in the presence of ISI. Simulation results show the gains of proposed SE-MOCZ in terms of spectral efficiency.
Description
Keywords
Modulation on Conjugate
Reciprocal Zeros (MOCZ), Spectrally-Efficient Modulation on Conjugate Reciprocal Zeros (SE-MOCZ), Short Packet Communications, URLLC, Faster-than-Nyquist Signaling
Citation
Degree
Master of Science (M.Sc.)
Department
Electrical and Computer Engineering
Program
Electrical Engineering