Multi‐layer interleave‐division multiple access: theory and practice

Abstract

SUMMARYDirect-sequence code-division multiple access (DS-CDMA) is often put on the same level with CDMA, ignoring the fact that many different CDMA techniques exist. A special CDMA technique which has recently become popular is interleave-division multiple access (IDMA). In this semi-tutorial, focus is on a generalisation of IDMA referred to as interleave-division multiplexing (IDM)/IDMA or multi-layer IDMA for short. Multi-layer IDMA is a special form of superposition coding, and can be interpreted as a joint modulation, channel coding and multiple access scheme. Motivated by information theoretical arguments and practical functionalities, a wide range of subjects (such as capacity bounds, power allocation, receiver analysis, quality of service aspects, multi-layer ARQ and possible applications) are covered. This semi-tutorial consists of three parts: in the first part, an introduction to IDMA (Section 1) and multi-layer IDMA (Section 2) is given. In the second part, practical issues such as functionalities of multi-layer IDMA (Section 3) and multi-layer ARQ (Section 4) are studied. In the third part, information theoretical bounds in conjunction with power allocation (Section 5) and a receiver analysis (Section 6) are provided, before conclusions are drawn in Section 7.

IDMA-based cooperative partial packet recovery: principles and applications

“…It is known that IDM features high spectral efficiency and flexible rate adaptation [21]. An IDM-based ARQ protocol is an efficient scheme for supporting multiple QoS requirements in the point to point communication systems [22]. Let b SkRu denotes the kth primary user's data sequence received by the uth cooperative secondary user, R u .…”

“…In this article, to address the utility issue, we propose a hybrid strategy and reveal applicability of the proposed partial packet recovery scheme to cognitive radio networks. In the proposed hybrid strategy, interleave division multiplexing (IDM) [21,22], a generalization of IDMA, is a spectral efficient scheme for the secondary users to gain more transmission time slots. IDM can be easily applied into our scheme for enhancing the throughput.…”

Triple-Polarized Multi-User Mimo-Idma System under Correlated Fading Channel

“…However increasing the number of antennas poses challenge in terms of space requirements since at least ten times the wavelength is the minimum required spacing between the antenna elements in case of a base station scenario. Also, the number of antennas is restricted to 4 and lesser due to size and energy considerations [19].…”

“…A single antenna based IDMA system employing BPSK-modulation and the corresponding channel estimation is studied in [18]. Further an extended IDMA system called multi-layer IDMA is proposed in [19]. The integration of orthogonal frequency-division multiplexing (OFDM) with IDMA and its benefits are discussed in [19]- [21].…”

“…Further an extended IDMA system called multi-layer IDMA is proposed in [19]. The integration of orthogonal frequency-division multiplexing (OFDM) with IDMA and its benefits are discussed in [19]- [21].…”