Interpolation based pilot‐aided channel estimation for STBC spatial modulation and performance analysis under imperfect CSI

Abstract

A combination of space-time block coding and spatial modulation (STBC-SM) has been recently proposed for multiple input-multiple output systems to obtain both spatial diversity gain and more capacity simultaneously while assuming the perfect channel state information (P-CSI) was available at the receiver. However, in practical scenarios the CSI is unknown to the receiver and should be estimated in order to detect the transmitted data in a reliable way. Therefore, channel estimation (CE) is a major challenge in designing the STBC-SM systems. In this study, the problem of CE is investigated and a new pilot-aided channel estimation (PA-CE) technique, coupled with an interpolation, is proposed for the STBC-SM systems operating in the presence of rapidly time-varying mobile channels. Several interpolation schemes such as the linear, nearest neighbour, piecewise cubic Hermite and the low-pass interpolations are applied and their performances are compared to determine the best suitable interpolation technique to be employed in STBC-SM systems. Bit error rate (BER) performance of the proposed CE technique is then investigated in time-varying channels with different modulation. Moreover, the pairwise error probability of the STBC-SM scheme is derived and its average bit error probability is evaluated analytically in the presence of CE errors.

Silicon content prediction of hot metal in blast furnace based on attention mechanism and CNN-IndRNN model

“…Based on the experience of experts, this paper makes a preliminary selection of forecast parameters. In order to ensure that the silicon content data and the predictive variables have the same frequency, the selected data is subjected to segmented three Hermite interpolation processing [12,13] . Finally, seven input variables for silicon content prediction were determined.…”

Channel estimation for OFDM-IM systems

“…Recently, channel estimation has been comprehensively studied in the literature for SM-based systems [8][9][10].…”

Novel OFDM System Using Orthogonal Pilot Symbols with Subcarrier Index Modulation

“…In [4], OFDM performance is presented for pedestrian and vehicular channel models, i.e., practical channels. Channel estimation (CE) techniques can be roughly divided up into two groups, i.e., using blind-way or pilot symbol aided (PSA) [5,6]. While blind channel estimation methods are based on second or higher order statistics; pilot-assisted channel estimation methods transmit a known signal, pilots, in both transmitter and receiver sides.…”

“…p n N N N N N  , and i c is the selected orthogonal pilot symbol according to index bits 2 b . Than by correlating received signal (7) with Walsh-Hadamard matrix C the orthogonal index of the orthogonal pilot code can be determined easily thanks to orthogonality of codes as follows: The proposed methods are first used to detect the index of Walsh-Hadamard codes as follows:response of channel at the pilot positions can be estimated by using least square (LS) method as ˆ( SPLINE interpolation technique is used in the process of constructing the whole channel response[6]. Then the first bits are demodulated according to the detection result in (7) using the look-up table for index of codes.…”