Implementation of MIMO data reordering and scheduling methodologies for eight‐parallel variable length multi‐path delay commutator FFT/IFFT

Abstract

The IEEE 802.11ac is the recently ratified standard developed for the fifth generation wireless fidelity technology, in which the multiuser (MU) multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) technique is adopted for the high data rate communication. In an MIMO-OFDM System, the forward/inverse fast Fourier transform (FFT/IFFT) processor is a key component. On proper reception, the reordering and scheduling of data is important for the optimal utilisation of butterfly resources in the pipelined FFT/IFFT processor. In this study, a mathematical model for an eight-parallel multimode (N = 512/256/128/64) multi-path delay commutator-based FFT/IFFT processor which is suitable for the IEEE 802.11ac compliant MU-MIMO-OFDM system is presented. On the other hand, the data reordering, scheduling methodologies and its architectures are proposed for the pre-, post-FFT/IFFT process are proposed. The design implementations are done using TSMC 65 nm complementary metal-oxide-semiconductor technology at 160 MHz. The power and area metrics with and without clock gating are compared. The clock gated implementation reports show that the power consumption is 17.44 mW for the pre-transformed data reordering and 11.64 mW for the post-transformed data reordering with an area occupation of 0.7694 mm 2 and 0.5111 mm 2 , respectively.

Variable length mixed radix MDC FFT/IFFT processor for MIMO‐OFDM application

“…Here, the data needs re-ordering before and after the FFT/IFFT operation. The input and output data re-ordering schemes are reported in our earlier work [19]. The input-data processing unit of Fig.…”

“…The input-data processing unit shown in Fig. 2 converts eight spatial streams of the serial data into the respective re-ordered data blocks [19].…”

“…16 and WPAN/WLAN/WMAN. In our earlier work [18,19], the pretransform and post-transform data scheduling, reordering methodologies for FFT/IFFT are presented to meet IEEE 802.11ac requirements.…”

“…Most of the FFT/IFFT designs reported so far in the literature are intended for the various applications like IEEE 802.11n/a/ad, IEEE 802.15, IEEE 802.16 and WPAN/WLAN/WMAN. In our earlier work [18, 19], the pre‐transform and post‐transform data scheduling, reordering methodologies for FFT/IFFT are presented to meet IEEE 802.11ac requirements.…”

Numerical Modelling of Structures with Uncertainties

“…The use of numerical techniques [1], [2], [3], [4], [5], in combination with the development of measurement techniques [6], [7], [8], [9], [10], [11], and the use of modern hardware [12], [13], provide opportunities to analyse more and more complex physical phenomena. Of special importance here is the progress in techniques used to create virtual models of real structures which model their behaviour in the best possible way [14], [15], [16], [17].…”