The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A new orthogonal space-time block coded (STBC) relay selection scheme over wireless cooperative network is presented. A system with four half-duplex relay nodes is considered in particular. We propose two different methods for use in the selection process. In the first method, the four relays are grouped into two subsets of two relays, each having identical encoding process in terms of the construction...
In coding theory, concatenated codes form a class of error-correcting codes that are derived by combining an inner code with an outer code. This is a solution to the problem of finding a code that has both exponentially decreasing error probability with increasing block length and polynomial-time decoding complexity. The work presented in this paper, provides link level performance analysis of non-line...
Combining coding, modulation, transmit and receive diversity, and validly increases the anti-noise performance in fading channels, OSTBC (orthogonal space-time block codes) is a new channel coding technology accompanying with the extensive application of wireless communication. Based on typical channel model of the OSTBC in MIMO (multiple-in, multiple-out) wireless communication channels, a general...
It has been proved that when the transmit power is sufficiently large distributed space time codes can achieve the maximal diversity order in a wireless relay network. In the previous works, space time codes used in a wireless relay network are limited on unitary space time codes or orthogonal (or quasi- orthogonal) space time codes. In this paper, we apply general multi-layer full-rate space time...
A non-coherent detection algorithm was proposed for orthogonal space-time coded multi-level continuous phase modulation (OST-MCPM) transmission systems of two transmit antennas, using a non-coherent maximum likelihood (ML) approach with different lengths of watch window. The noncoherent detection algorithm is suitable for any number of receive antennas and the receiver does not need to estimate the...
In this paper, we present a new robust scheme for use in asynchronous cooperative networks over frequency-selective channels through using three and four relay nodes. Based on extended orthogonal space-time block coding (EO-STBC), we have presented a direct quantized feedback approach that can achieve full cooperative diversity and array gain with unity code rate over each hop. In this scheme, we...
In this paper, we analyze the performance of dual-hop channel state information (CSI)-assisted amplify-and-forward (AF) cooperative networks using orthogonal space-time block codes (OSTBCs) over independent but not identically distributed Nakagami-m fading channels. Specifically, we present closed-form expressions of the outage probability (OP) and the symbol error probability (SEP). The analytical...
The paper investigates the average pair-wise error probability (PWEP) performance of orthogonal space-time coded MCPM (OST-MCPM) systems for two transmit antennas over independent and correlated channels. Simple upper boundary expression at high SNR is derived to evaluate the PWEP in correlated channel. The achievable diversity gain of this system decreases due to the signal correlation between the...
The use of differential coding is proposed in hybrid pulse interval modulation-optical code division multiple access (hPIM-OCDMA) for optical wireless communication systems. In hPIM-OCDMA, although the 2m-ary symbol modulates the interval between pulses, the interval is vulnerable to multiple access interference (MAI), which can cause false-alarm pulses, resulting in consecutive errors in symbol detection...
Localization has many important applications in wireless sensor networks. A variety of wireless technologies, such as acoustic, infrared, and ultra-wide band (UWB) media have been applied for localization purposes. This paper consists of two parts. The first part presents new UWB-based communication protocols for received signal strength (RSS) information collection, namely, a robust UWB coding method...
A kind of quasi-orthogonal space time block code for decode-and-forward relay networks is analyzed in this paper. At the source, 4 single-antenna users transmit the quasi-orthogonal space time block code matrix. At the relay node, maximum-likelihood decoding algorithm is adopted and the decoded symbols are then encoded into quasi-orthogonal code which is transmitted through transmit antenna. At the...
This paper aims to present the results that can be obtained with a conventional multiuser detector used in conjunction with turbo encoding in order to improve its performance, evaluated in terms of bit error rate (BER) as a function of signal to noise ratio (SNR). We used extensive Monte Carlo simulations, taking into consideration different combinations with respect to the number of users, the cross-correlation...
The proposed singular value decomposition (SVD) aided spatial multiplexing (SM) based multiple-input-multiple-output (MIMO) system is capable of achieving a high bandwidth efficiency. The SVD operation effectively splits the MIMO channel into orthogonal eigen-beams having unequal bit-error-ratios (BERs). This property may be exploited for the transmission of speech, audio, video and other multimedia...
In this paper, coded modulation technique based on the use of convolutional self-doubly orthogonal codes (CSO2C) and threshold iterative decoding is presented. Two different methods of coded modulation are considered. The first approach is based on a conventional pragmatic scheme. In the second approach, all information bits are coded and a simpler Gray coding is used for the bit-to-symbol mapping...
In this paper, distributed double-differential coding is proposed to avoid the problem of carrier offsets in amplify and forward protocol based cooperative network with two relays. A double-differential orthogonal-space-time block code is transmitted by the relays in a distributed manner without channel knowledge. We derive a low complexity linear decoder which does not require the channel and carrier...
In this paper eigen-beamforming and differential space-time modulation (DSTM) are combined together to construct a robust and relatively simple system for multiple-input multiple-output (MIMO) Ricean fading channels. A transmission scheme with feedback link is developed here that combines beamforming with differential multi-antenna modulation based on orthogonal space-time block coding. The power...
In this paper, we first analyze the amount of fading (AF) of orthogonal space-time block codes (STBCs) over spatially uncorrelated keyhole channels. In order to investigate the diversity order of keyhole channels, we then derive an approximate expression for the average bit error rate (BER) at high signal-to-noise ratio (SNR). Finally we present the average capacity expression by applying the Gauss-Laguerre...
Starting from three transmit antennas and Nr receive antennas (3Tx-Nr Rx, generally defined as MIMO) system employing orthogonal space-time block coding (STBC-MIMO), the paper analyzes the solution procedure of complex orthogonal weighting channel matrix (OWCM) and decoupling method of the signals received for the resulting pre-coding system, and concludes an algorithm process using computer simulation...
This paper investigates the effect of nonlinear power amplifiers (NLPA) on orthogonal space-time coded multi-level continuous phase modulation (OST-MCPM) transmission systems with two transmit antennas. The maximum likelihood sequence detection (MLSD) is applied to OST-MCPM systems. Simple upper bound of the pair-wise error probability (PWEP) is derived to evaluate the achievable diversity gain in...
The CI-OFDM (carrier interferometry orthogonal frequency division multiplexing) CI-OFDM system spreads each information symbol across all N sub-carriers using orthogonal CI spreading codes. The CI-OFDM system can show the advantage of PAPR (peak to average power ratio) reduction and frequency diversity gains without any loss in the communication throughput. In this paper, focusing on the two Tx (transmit)...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.