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Modulation classification is a technique to achieve blind estimation of modulation types. Thereby, signaling overhead can be reduced or equivalently spectrum efficiency can be improved. However, the benefit is limited in coded systems, since the code rate information have to be signaled anyway. To fulfill the requirement of higher spectrum efficiency in 5th generation (5G) systems, a method of constellation...
The combination of multiple-input multiple-output (MIMO) and orthogonal frequency-division multiplexing (OFDM) is a promising solution for high-data-rate transmission. An architecture of a K-best based list sphere detector (LSD) algorithm for a MIMO-OFDM system is introduced in this paper. The architecture was designed for a 2 × 2 antenna system with quadrature phase shift keying (QPSK) and 16-quadrature...
With growing demand of machine to machine (M2M) communication, wireless communication systems request simultaneous connections for many terminals to cope with thus increasing communication throughput. We focus on interleave division multiple access (EDMA) that has superior user detection performance and describe a VLSI design of an interference canceller that performs user detection in QPSK OFDM-IDMA...
This paper presents a performance evaluation of OFDM LTE downlink physical layer according to the latest 3GPP specifications. Particularly, adaptive modulation and coding (AMC) is described and analyzed. This is in conjunction with the turbo decoding algorithm Max-Log-Maximum A Posteriori (Max-Log-MAP) used in soft input soft output (SISO) decoders. The performance analysis is carried out in terms...
In the paper, an improved link adaptation scheme is proposed for the WiMedia MB-OFDM UWB system, in which quality of service (QoS) support is provided. The proposed scheme consists of three functional blocks: link quality indicator (LQI) calculator, frame error rate (FER) estimator, and transmitter (TX) parameter selector. Instead of using the average receive SNR (ASNR) as LQI, a new LQI metric is...
In this paper a new method for uplink inter-cell interference coordination (ICIC) in a full frequency reuse system is proposed. The technique is named uplink interference protection (ULIP). ULIP exploits existing reference signals transmitted by all base stations (BSs). The fact that path loss and lognormal shadowing can be considered reciprocal in such frequency-division duplex (FDD) systems is exploited...
The creation of Ultra-Wideband (UWB) radio platform has allowed the development of high bit-rate Wireless-USB offering High Definition video streaming. Quadrature Phase Shift Keying (QPSK) and Dual Carrier Modulation (DCM) are the current modulation schemes used for Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) in the ECMA-368 defined UWB radio platform. ECMA-368 offers up to 480...
Wireless connectivity will become an integral component of the aircraft cabin in the near future. For the planning of the reliable network a detail analysis of the coverage is required. This paper observes the coverage in an aircraft cabin for an OFDM UWB system based on the ECMA-368 standard. For this purpose, based on real measurement in an airplane cabin mock-up, a Saleh-Valenzuela channel model...
This paper presents evaluation on avoidance capability of a tunable notch filter (TNF) in IR-UWB systems. The TNF enables to control the frequency where a single frequency notch is generated by changing the DC voltage into the capacitance in the TNF. We showed test results on coexistence between QPSK and IR-UWB systems. The results show that the TNF successfully avoids the interference from the UWB-IR...
The large amount of unlicensed bandwidth available in the millimeter-wave has enabled very high data rate wireless applications. The IEEE 802.15 Task Group 3c has completed standardization efforts for multi-gigabit data rate communications on both the physical (PHY) and medium access control (MAC) layers. This paper presents a performance evaluation of the PHY and MAC layers of the newly published...
In this paper, we report on a mobile broadband wireless access (MBWA) system field trial with Fast Low-latency Access with Seamless Handoff Orthogonal Frequency Division Multiplexing (FLASH-OFDM), which was carried out at Sendai city in Japan. This paper describes coverage estimates of an uplink 16 quadrature amplitude modulation (QAM) signal under the condition of constant terminal output power when...
In this paper, we report on a mobile broadband wireless access (MBWA) system field trial with fast low-latency access with seamless handoff orthogonal frequency division multiplexing (FLASH-OFDM), which was carried out at Sendai city in Japan. This paper discusses the feasibility of uplink transmission with the maximum modulation level of 64 QAM, using the measured uplink throughput performances when...
Dual-hop transmission is a technique by which the channel from the source to the destination is split into two possibly shorter links using other nodes. The source transmits signals to the destination via a group of nodes that act as relays. It is an effective technique when the direct link between the source and the destination is in deep fading, severe shadowing, or non-line-of-sight (NLOS) environment...
In the near future, wireless connectivity will become a commodity in aircrafts. For the planning of the reliable network a detail analysis of the coverage is required. This paper studies the coverage in an AIRBUS A380 cabin for a OFDM UWB system based on the ECMA 368 standard. For this purpose, based on real measurement in an AIRBUS A380 airplane cabin, a Saleh-Valenzuela channel model and a path-loss...
3GPP LTE is the evolution of UMTS which will make possible to deliver next generation high quality multimedia services according to the users' expectations. The flexibility of the downlink OFDM radio interface with Adaptive Modulation and Coding (AMC), MIMO and H-ARQ plays a crucial role in achieving the low latency and high spectral efficiency promised by the new radio access standard. This paper...
This paper presents a multi-UWB-OFDM PHY layer system enable to operate in UWB spectrum mask and at 60 GHz considering two PHY layer systems ensuring a backward compatibility themselves. It allows large throughput scalability and frequency resource management. The system considers on the one hand enhanced baseband processing for ECMA-368 based on advanced binary interleaving techniques. The second...
In accordance with the channel status information, modulation and coding method can be changed adaptively to enhance the throughput in Long Term Evolution Time Division Duplexing (LTE TDD) system. With the scheme of Exponential Effective SNR Mapping (EESM) and Mutual Information Effective SNR Mapping (MIESM), two Adaptive modulation and coding mechanisms are proposed in this paper. Simulation results...
AMC (adaptive modulation and coding) is an important technology adopted by IEEE 802.16. Based on AMC, we introduce a frequency domain scheduling and subchannel resource allocation algorithm (FDSA) in this paper for IEEE 802.16 OFDMA systems. According to this algorithm which is applied in physical layer, the paper also proposes a simple AMC link adaptive mechanism. In different conditions, the throughput...
This paper presents WiMax system performance results especially spectral efficiency and throughput under severe multi-path fading and noisy channel conditions. These results are obtained by simulating enhanced WiMax physical layer models with and without transmit diversity. The system behavior is shown to be marginal for modulations beyond 16-QAM under worse conditions necessitating the mandatory...
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