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Although the Z-domain precoding method for blind separation of spatially correlated sources is proved reliable in theory, it has disadvantages in its implementation since it requires knowledge of precoder zeros at the receiver beforehand. A new method is proposed in this article to find these precoder zeros and estimate the separation vectors of the coded signals at the same time by exploiting the...
Nowadays, millimeter-wave communication centered at the 60 GHz radio frequency band is increasingly the preferred technology for near-field communication since it provides transmission bandwidth that is several GHz wide. The IEEE 802.11ad standard has been developed for commercial wireless local area networks in the 60 GHz transmission environment. Receivers designed to process IEEE 802.11ad waveforms...
Millimeter wave (mmWave) is one of the key technology in the fifth generation mobile communication system. In mmWave system, hybrid precoding is applied to reduce the number of radio frequency (RF) chains. Although narrow band multiuser hybrid precoding is widely studied, only a few works focus on wideband hybrid precoding. The main problem is that all subcarrier share the same analog precoding matrix...
In this paper, we analyze uplink sum rate of multiple-input multiple-output (MIMO) systems with maximum-ratio combining (MRC) receivers. To be practical, receive correlation and different powers of users are assumed. Two novel approximate results on sum rate are derived in closed form. Based on the results, we also obtain the asymptotic results on sum rate when the number of base station antenna (M)...
Due to the unreliable nature of wireless links, sensor nodes frequently encounter degraded performance or lack of connection. This paper provides a real-time status monitoring and channel error diagnosis method in a wireless sensor network. It uses a poll and echo procedure to efficiently collect some physical layer and link layer statistics from both transmitter side and receiver side. A machine...
Satellite based positioning systems like GPS (Global Positioning System) exist in every moment of our lives. GPS signal is broadcasted by Link1 (L1) and Link2 (L2) frequencies, separately. L1 is assigned to civil users, while L2 is especially for military users. GPS signal consists of navigation message and PRN codes (C/A for civil and P-code for military) which is an identity for satellite. PRN codes...
This paper studies the fundamental limits of caching in a network with two receivers and two files generated by a two-component discrete memoryless source with arbitrary joint distribution. Each receiver is equipped with a cache of equal capacity, and the requested files are delivered over a shared error-free broadcast link. First, a lower bound on the optimal peak rate-memory trade-off is provided...
A constant-amplitude output signal for the Zadoff-Chu sequence was used for the low complexity MANET transmitter devices to improve safety of autonomous cars. The main goal is to merge the communication block and the obstacle detection block in singular multipurpose device. The article presents the algorithm of using the Zadoff-Chu sequence to establish the initial synchronization for the joint communication...
This paper focuses on the estimation of target's motion parameters in a moving transmitter/moving receiver forward scatter radar scenario. An extension of the quasicoherent processing initially developed for stationary FSR mode of operation is introduced. This offers an estimation of the target's trajectory in a general case where transmitter and receiver can be moving. Simulated and real data are...
This paper investigates the Gaussian state-dependent Z-interference channel (Z-IC), in which two receivers are corrupted respectively by two correlated states that are noncausally known to transmitters and unknown to receivers. Three interference regimes are studied, and the capacity region or sum capacity boundary is characterized either fully or partially under various channel parameters. The impact...
This paper is concerned with the design of capacity approaching ensembles of Low-Density Parity-Check (LDPC) codes for correlated sources. We consider correlated binary sources where the data is encoded independently at each source through a systematic LDPC encoder and sent over two independent Gaussian channels. At the receiver, a joint iterative decoder consisting of two component LDPC decoders...
Antenna correlation is prevalent in higher frequencies as well as in massive MIMO, thus the study of correlated MIMO broadcast channels is becoming a subject of increasing interest. This paper explores the fundamental limits of such systems, focusing on cases where correlation eigenspaces are neither independent nor identical, so that known beam-space division techniques do not directly apply. We...
A novel method for distance estimation is introduced, based on an OFDM signal combined with the Zadoff-Chu Sequences. By exploiting the properties of these sequences it is possible to evaluate the distance between a transmitter and a receiver with a very good precision and accuracy. The technique effectiveness is demonstrated in a real operating environment by measuring the distance between two active...
Providing short-message communication and simultaneous channel estimation for sporadic and fast fading scenarios is a challenge for future wireless networks. In this work we propose a novel blind communication and deconvolution scheme by using Huffman sequences, which allows to solve three important tasks at once: (i) determination of the transmit power (ii) identification of the instantaneous discrete-time...
With the development of investigation technology, stealthy performance of modern LPI radar is not only related to the signal waveform, but also related to the signal processing methods the intercept receiver used. Using the most common signal processing methods extract the signal feature, and distinguish them by Neural Networks algorithm, take the recognition rate results as the metrication of LPE,...
Cognitive radio system is a context-aware technology in communications. Spectrum sensing is an important function in the implementation of cognitive radio systems by detecting the presence or absence of primary users within the frequency spectrum and makes available free channels for secondary users. Cyclostationary Feature Detector is capable of detecting signals at low signal to noise ratios relying...
Indoor-outdoor (IO) detection provides very useful hints for a mobile device to perform context-aware services. To that end, GPS presents a viable solution by relating a device's IO status with its positioning performance, which depends on the device's exposure to the open sky. This approach, however, is prohibitively expensive in terms of energy consumption and response time. Recent work has thus...
This paper presents a method of enhancing the aperture size and the effective number of elements of a millimeter wave radar array to make it competitive and complementary as an imaging system for collision avoidance and imaging in adverse environments. We increase aperture size by using a Vernier geometry, with a MIMO overlay to provide adaptive beamforming and multi-target tracking. We reduce the...
This paper explores new multicarrier signals and systems for 5G; spectrally efficient frequency division multiplexing (SEFDM), in which higher spectral efficiency (SE) compared to conventional orthogonal frequency division multiplexing (OFDM) is achieved by violating the orthogonality of its subcarriers. This work proposes new system and receiver models and then investigates the employment of various...
Growth in telecommunication world leads to an increase in the importance of efficient usage of frequency spectrum. Increasing number of subscribers and their demands force network operators to use the frequency bands as efficiently as possible. It is necessary to detect and prevent the interference of secondary or unauthorized frequency band occupations. Cyclostationary signal analysis is widely used...
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