Massive Multiple Access Based on Superposition Raptor Codes for Cellular M2M Communications

Abstract

Machine-to-machine (M2M) wireless systems aim to provide ubiquitous connectivity between machine type communication (MTC) devices without any human intervention. Given the exponential growth of MTC traffic, it is of utmost importance to ensure that future wireless standards are capable of handling this traffic. In this paper, we focus on the design of a very efficient massive access strategy for highly dense cellular networks with M2M communications. Several MTC devices are allowed to simultaneously transmit at the same resource block by incorporating Raptor codes and superposition modulation. This significantly reduces the access delay and improves the achievable system throughput. A simple yet efficient random access strategy is proposed to only detect the selected preambles and the number of devices which have chosen them. No device identification is needed in the random access phase which significantly reduces the signalling overhead. The proposed scheme is analyzed and the maximum number of MTC devices that can be supported in a resource block is characterized as a function of the message length, number of available resources, and the number of preambles. Simulation results show that the proposed scheme can effectively support a massive number of M2M devices for a limited number of available resources, when the message size is small.

Aggregation and Resource Scheduling in Machine-Type Communication Networks: A Stochastic Geometry Approach

“…channel is given in (2) at the top of the page. 3 There are some solutions using NOMA for the random access stage as well, e.g., [17], [32]. In fact, the work in [32] proposes a NOMA scheme where the devices transmit their messages over randomly selected channels, while the random access and data transmissions phases are combined.…”

“…3 There are some solutions using NOMA for the random access stage as well, e.g., [17], [32]. In fact, the work in [32] proposes a NOMA scheme where the devices transmit their messages over randomly selected channels, while the random access and data transmissions phases are combined. Readers will realize that our resource scheduling schemes can be easily incorporated to that strategy to improve the overall system performance; however, the details of such implementation are out of the scope of this work.…”

“…Proof. Note that (a) comes directly from the total probability theorem, and also averaging p Also, mod (k, N) = k − N if N + 1 ≤ k ≤ 2N − 1, and the approximation is because we substituted the infinite sum for a finite sum until k max to reach (32).…”

Virtual Carrier Sensing-Based Random Access in Massive MIMO Systems

“…As a result, grant-free RA schemes are now being considered as a low-signaling-overhead alternative for RA. This type of scheme has been propounded first in [11] and other similar schemes were developed in [12]- [14]. These schemes, via code-domain multiplexing, are able to reduce transmission latency and increase RA capacity to a certain degree.…”

GFDM Frame Design for 5G Application Scenarios

“…Ultra Reliable Low Latency (URLL) applications, also known as Tactile Internet [2], requires latency below 1 ms and robustness in order to avoid packages retransmissions. The Internet of Things (IoT) and Machine-Type Communication (MTC) will demand connectivity of a massive number of energy-limited devices per cell [3], which cannot afford cumbersome synchronization process with the network. Internet Access for Remote Areas (IARA) is the last frontier for universal connectivity and 5G must present a operation mode capable of supplying Internet connect in remote/rural areas, where the cell coverage must be bigger than 50 km [4] and, therefore, over a doubly-dispersive channel [5].…”