Ibra Dioum

A Novel Compact Dual-Band LTE Antenna-System for MIMO Operation

In this communication, we present a novel compact dual-band antenna-system for LTE multi-input and multi-output (MIMO) mobile handsets. The radiators consist of 3D Inverted-F- Antennas (IFAs) folded on the non-metalized part of the Printed Circuit Board (PCB) and operating in the LTE 700 MHz band. A parasitic radiating element is also attached to the IFAs to operate in the LTE 2.5-2.7 GHz band. Two antennas are placed on a realistic PCB (100 × 40 mm2) for MIMO operation. Various antenna configurations are tested when moving their position on the PCB. Based on the highest port-to-port isolation criterion, two configurations are adopted and their performances are compared. Both simulated and measured results are shown to illustrate the MIMO capabilities of the proposed structures.

Compact dual-band monopole antenna for LTE mobile phones

In this paper, we present a dual-band antenna for Long Term Evolution (LTE) handsets. The proposed antenna is composed of a meandered monopole operating in the 700 MHz band and a parasitic element which radiates in the 2.5–2.7 GHz band. Two identical antennas are then closely positioned on the same 120×50 mm2 ground plane (Printed Circuit Board) which represents a modern-size PDA-mobile phone. To enhance the port-to-port isolation of the antennas, a neutralization technique is implemented between them. Scattering parameters, radiations patterns and total efficiencies are presented to illustrate the performance of the antenna-system.

Soft output detection for MIMO systems using binary polar codes

Polar codes are proven capacity-achieving and are shown to have equivalent or even better finite length performance than turbo/LDPC codes under some improved decoding algorithm over the Additive White Gaussian Noise (AWGN) channels. Polar coding is based on the so-called channel polarization phenomenon induced by a transform over the underlying binary-input channel. The channel polarization is found to be universal in many signal processing problems and is applied to the coded modulation schemes. In this paper, a small length polar, encoded for a MIMO (Multiple-Input Multiple-Output) systems with soft output MMSE-SIC (Minimum Mean Square Error-Successive Cancellation) detection, is applied to improve the coded performance while reducing the complexity. In order to prove this theory, we compare the proposed MMSE-SIC BER to Zero Forcing (ZF) and Maximum Likelihood (ML) by using 2*2 MIMO systems into Rayleigh channel with BPSK (Binary Phase-Shift Keying) modulation. Simulation results show that MMSE-SIC complexity is lower than the two others detections. We show that the performance of the proposed approach using polar code (128, 64) at 10−2 BER (Bit Error Rate) is around 3dB i.e. 0,66% compared to the optimal ML, while ZF performance is the worst.

Study of polar codes MIMO channels polarization using MIMO system

Polar codes are known as the first provable code construction to achieve Shannon capacity for arbitrary symmetric binary input channels. Several schemes to provides both detection/decoding of the transmitted and the transmit antenna index in Multiple-Input Multiple-Output (MIMO) antenna systems were proposed in the literature for polar codes. In this paper we have critically analyzed various MIMO channel polarization using polar codes extended to the multiple antenna transmission, and also have covered free polar set and frozen polar set for respectively mapping transmitted information and transmit antenna index.

Evaluation of the MIMO performance of LTE handsets

In this paper, we present the design and the evaluation of two MIMO antenna structures for LTE handsets. We first measure their scattering parameters and then we simulate their MIMO performance (channel capacity and Block Error Rate) in two different environments (channel models) with the help of the Agilent SystemVue Software.

Small Polar Codes Concatenating to STBC Applied to MIMO Systems

This paper uses a concatenation of small Polar Codes length (N=32) and Space Time Block Code, this Polar-STBC is applied to no diversity (SISO), SIMO, MISO and MIMO systems. Minimum Mean Square Error using Successive Interference Cancellation (MMSE-SIC) is a soft output used to the receiver in order to improve Bit Error Rate (BER) and finally Successive Cancellation Decoder (SCD) is placed to the decoder in order to improve the BER and Frame Error Rate (FER). Comparison between several STBC without concatenation schemes and this small Polar-STBC shown that the proposed allows minimizing the BER and FER performances.

Free Space Passive Optical Network

This paper proposes free space passive optical network (FSPON) as a potential candidate of high data rate access network based on optical wireless transmission. FSPON could be considered for indoor as well as outdoor deployments. Pending the progress in FSO range, it is appropriate for short range communication network. The system architecture and network architecture are depicted. A key component for the deployment success is the alignment of the remote terminal equipment’s with the free space optical splitter (FSOS). The main advantages and performances of a user terminal station are discussed. The performance comparison has been made with a simple point to point free space optical link. The FSPON capacity is limited to 6 users at the cost of low modulation scheme and high signal to noise ratio.

Increase MIMO Systems Performances by Concatenating Short Polar Codes to Spatial Time Block Codes

Polar codes, proposed by Erdal Arikan, have attracted a lot of interest in the field of channel coding for their capacity-achieving trait as well as their low encoding and decoding complexity in order O (NlogN) under successive cancellation (SC) decoder. However, there remains one significant drawback, that is, the error correction performance of short and moderate length polar codes is unsatisfactory, especially when compared with low-density parity check (LDPC) codes and turbo codes. In this paper, we propose a concatenation scheme performance, which employs a short polar encoder following to Spatial Time Block Codes (STBC), and we develop an efficient detector for Multiple Input Multiple Output (MIMO) antennas, which adaptively combines Minimum Mean Square Error Successive Interference Canceller together (MMSE-SIC). We also compared to Maximum Likelihood in the literature and finally present a simulation results in binary input Additive White Gaussian Noise (BI-AWGN) with binary phase shift keying (BPSK) modulation, and we observe that, our proposed concatenation scheme significantly outperforms the Maximum Likelihood performance in the high Signal-to-Noise-Ratio (SNR).

Limits of relays in cascade for wireless optical communications networks

Turbulence is one key limitation factor of wireless optical transmission. In this paper a combined modulation and relays schemes as solutions to extend the free space optics (FSO) range are studied. The objective were to find the limitations in wireless communication range extension. Since turbulence limits the communication link of wireless optical communication, coding and diversity are considered as potential solution to overcome this limitation. Decode and forward (DF) relays and two modulations scheme as pulse position modulation (PPM) and multi pulse position modulation are addressed. It has been estimated the number of relays with efficient performance for PPM and MPPM.