Radar-communication Integration Research Articles

Weak Target Integration Detection Based on Radar Communication Integrated Signal via Constructed Step-LFM Model

Weak Target Integration Detection Based on Radar Communication Integrated Signal via Constructed Step-LFM Model

Power Resource Allocation Algorithm for Dual-Function Radar–Communication System

In this paper, a power allocation algorithm of dual-function radar–communication system with limited power is proposed to obtain better overall system performance measured by the weighted summation of radar signal to interference plus noise ratio (SINR) and communication channel capacity. First, a power allocation model is established to maximize the radar SINR and communication channel capacity with limited transmitted power. Then, the Karush–Kuhn–Tucker (KKT) conditions are used to solve the optimal objective function under the condition that only radar SINR or communication channel capacity is considered, respectively. Finally, the optimal value is combined with the original model and transformed into a single objective optimization model, and the optimal power is obtained by solving the model through the iterative optimization algorithm. Simulation results show that, compared with other power allocation algorithms, the proposed algorithm can achieve better radar-communication integration performance under the same transmit power.

Challenge and Prospect of High-speed Rail Radar Communication Integration Technologies

Radar plays an important role in urban public transit system, so it is of great significance to ensure the safe operation of High-speed rail. Radar communication integration technology has the characteristics of high efficiency and low energy consumption, it can improve communication quality, speed up transmission efficiency and improve detection accuracy. Firstly, this paper introduces the running scene of High-speed rail, and puts forward that radar communication integration technology has a broad application space in High-speed rail. Then it introduces radar communication integration technology, and the research status, advantages and development prospects of radar communication integration technology based on linear frequency modulation（LFM）. Finally, it is proposed that obstacle detection technology is one of the difficulties to ensure the safe operation of High-speed rail. Radar integration technology can be effectively applied to train obstacle detection, which is an important technical support for improving service quality and speeding up the intelligent construction of High-speed rail in the future.

Integrated Waveform Design Based on UAV MIMO Joint Radar Communication

The problem of orthogonal waveform construction in multiple input/multiple output (MIMO) radar communication integration greatly limits the realization of integration technology. In the unmanned aerial vehicle (UAV) MIMO antenna scenario, an orthogonal integrated waveform suitable for a MIMO antenna is designed using a sub−LFM−BPSK waveform combined with a chaotic spread spectrum code. After spread spectrum processing, each MIMO antenna transmits different communication data for orthogonal spread spectrum processing, which is suitable for the omnidirectional detection of MIMO application scenarios; moreover, the closed-form expressions of the integrated orthogonal waveform under certain constraints are derived. Finally, the simulation proves that the integrated orthogonal waveform set in the UAV MIMO scenario has excellent radar detection and communication capabilities.

Integrated Radar and Communication Design With Low Probability of Intercept Based on 4-D Antenna Arrays

In recent years, there are increasing interests and applications on radar–communication integration for system miniaturization, cost reduction, and so on. Moreover, thanks to the common functions of hardware components including transceiver, antennas, and even basic signal/data processing, the integrated design of radar and communication systems becomes feasible. In this article, through design of proper time sequences, waveforms, and recognition algorithms, radar sensing and wireless communication can be integrated into 4-D antenna arrays simultaneously. In addition, with the high design degrees of freedom of 4-D arrays, the proposed approach can also provide a low probability of intercept capability. Selected numerical and experimental results are provided to validate the effectiveness of the proposed approach.

Radar–Communication Integration for 6G Massive IoT Services

The world is entering a new era with ubiquitous connectivity among billions of humans and machines, i.e., the sixth-generation (6G) massive Internet of Things (IoT). Radar and communication need to be integrated into this system to achieve target detection and massive connectivity. In this work, we first develop a shape-adaptive antenna array composed of multiple subarrays spaced at regular intervals. The shape-adaptive antenna array uses flexible material that enables changes in the physical structure to achieve adaptive gain. Subsequently, we investigate the micromovement of IoT targets, such as the micro-motion characteristics and micro-Doppler effects of rotary-wing drones. The simulation results demonstrate the effectiveness and efficiency of the proposed schemes for detecting unmanned aerial vehicles (UAVs) in an IoT scenario.

Design of h--CPM-LFM Radar-Communication Integration Signal

Design of h--CPM-LFM Radar-Communication Integration Signal

Power Loss Suppression for Time-Modulated Arrays in Radar-Communication Integration

In order to minimize the weight and volume of the radio frequency equipment while alleviating the shortage of spectrum resources, electronic system integration has become a topical area in both civil and military fields, and the radar-communications integrated technology based on the time-modulated array (TMA) has also been proposed due to its low complexity and easy reconfiguration property. The TMA has power losses caused by sideband signals radiation, which is inherent drawback. However, existing TMA power loss optimization methods are not suitable for radar-communication integration, because of the existence of multiple harmonic components. In this paper, a closed-form expression of TMA power losses for radar-communications integration is derived and the sideband radiation is optimized. Firstly, some preliminaries about TMA are shown. Then, the radar-communications integration strategy based on TMA is introduced. Moreover, a closed-form expression of TMA power losses caused by sideband signals radiation is derived, and the direct power losses optimization method is proposed based on the derived results. Finally, the theoretical results are validated by simulations.

Research Status and Development Trend of Radar Communication Integration

Research Status and Development Trend of Radar Communication Integration

Key Technologies in 6G SAGS IoT: Shape-Adaptive Antenna and Radar-Communication Integration

6G will integrate the physical and digital worlds, and ubiquitous 6G service will seamlessly reach users worldwide. The concept of space-air-ground integrated networks has been proposed to integrate these three subnetworks homogenously. However, the ocean accounts for about 71 percent of the global area, and underwater networks play an important role in the defense field and the construction of the intelligent marine Internet of Things. To seize future development opportunities, this article introduces the space-air-ground-sea integrated network (SAGSIN) and related technologies, including the shape-adaptive antenna and radar-communication integration. The proposed shape-adaptive antenna is made of flexible materials, thereby allowing its physical shape to be changed in real time and for a specific radiation beam to be formed according to the functional requirements. The requirements and feasibility of radar communication integration are also analyzed comprehensively, and a detailed analysis and simulation verification are carried out for UAV detection.

Efficient Data Transmission Strategy for IIoTs With Arbitrary Geometrical Array

Various kinds of data are generated from industrial Internet of Things, and these data can be applied for connecting production equipment, identifying and locating items, etc. These data should be forwarded to the decision center for further analyses, especially in wartime. Thus, the channel status information (CSI) for industrial big data transmission has to be acquired. In this article, we develop a system architecture for industrial big data (BD) transmission based on radar-communication integration with arbitrary geometrical array. The traditional channel estimation method, which usually utilizes the regular antenna array to estimate the CSI, cannot be applied to the arbitrary geometrical array. Here, we use the manifold separation technique to transform the complex array configuration into regular array and the downlink channel covariance matrix is estimated by exploiting the frequency calibration technique when the uplink channel covariance matrix is received. The computational complexity for the proposed method and other state-of-the-art methods are analyzed. The simulation results prove that the proposed method can achieve excellent estimation performance for its application in radar-communication integration.

Analysis and Optimization of Ambiguity Function in Radar-Communication Integrated Systems Using MPSK-DSSS

With increasingly sophisticated electromagnetic environment of combat platforms, radar communication integration has attracted wide interests. In this letter, instead of designing a new integrated signal, we employ multiple-phase shift keying direct sequence spread spectrum (MPSK-DSSS) signal as radar communication integrated signal due to its advantage of outstanding correlation. On the one hand, the closed form expression of average ambiguity function is obtained, by which we can analyze the relationship between parameters of integrated signal and radar range resolution. On the other hand, to improve radar peak sidelobe level (PSL) influenced by random communication signals, we propose a joint optimization method based on sequence mapping at the transmitter and sidelobe suppression at the radar receiver. Simulation results show that the sidelobe levels of the optimized integrated signal is effectively suppressed at the cost of slight communication rate loss.

Experimental verification of an integrated radar communication system

With the development of modern weapon techniques, radio frequency integrated technology has attracted widespread attention as a key technology to improve the informationalised level of missiles. Radar and communication are two typical electronic types of equipment, and their integration can support and promote the development of radio frequency integrated technology. In this study, experimental verification of an integrated radar–communication system is carried out. Firstly, the key technologies to achieve radar–communication integration are theoretically analysed. The solutions of the key issues, including signal separation, time synchronisation and frequency synchronisation, are proposed. Furthermore, a radar–communication demo is implemented and the experimental verification is carried out here to verify the feasibility of the proposed methods.

Research on reducing PAPR of QAM‐OFDM radar‐communication integration sharing signal

In order to solve the problem of high peak-to-average power ratio (PAPR) of the sharing signal for radar-communication integration based on quadrature amplitude modulation-orthogonal frequency division multiplexing modulation, according to the theoretical model of the sharing signal, the authors analyse the PAPR, subsequently employing the active constellation extension algorithm to suppress the PAPR of the sharing signal. The simulation results show that, with designing the number of iterations reasonably, the active constellation expansion algorithm will effectively reduce the PAPR of the sharing signal. Meanwhile, for radar sub-systems, the target detection performance and the transmitter power are less affected. For communication sub-systems, the error vector magnitude is small, and the bit error rate of the system is comparable to the original signal.

A Novel Scheme for MIMO-SAR Systems Using Rotational Orbital Angular Momentum.

The vortex electromagnetic (EM) wave with orbital angular momentum (OAM) brings a new degree of freedom for synthetic aperture radar (SAR) imaging, although to date, its application to multi-input multi-output (MIMO) SAR has not yet been widely reported. In this paper, an orbital angular momentum (OAM)-based MIMO-SAR system is proposed. The rotational Doppler Effect (RDE) of vortex EM waves offers a novel scheme for an OAM-based MIMO-SAR system. By transmitting the rotational vortex EM waves, echoes of different OAM modes can be discriminated by a bandpass filter in the range-Doppler domain. The performance of the proposed scheme is independent of the time-variant channel responses, and the wider beam width of the vortex EM waves delivers, for the same antenna aperture size, better performance in terms of swath width and azimuth resolution, in contrast to the plane EM waves. Moreover, the spatial diversity of vortex EM waves shows great potential to enhance the MIMO-SAR system applications, which involve high-resolution wide-swath remote sensing, 3-D imaging, and radar-communication integration. The proposed scheme is verified by proof-of-concept experiments. This work presents a new application of vortex EM waves, which facilitates the development of new-generation and forthcoming SAR systems.

Radar Communication Integrated Waveform Design Based on OFDM and Circular Shift Sequence

Based on the orthogonal frequency division multiplexing (OFDM) technique, an intelligent waveform is designed, which is suitable for simultaneously performing data transmission and radar sensing. In view of the inherent high peak-to-mean envelope power ratio (PMERP) and poor peak-to-side-lobe ratio (PSLR) problems in the OFDM based radar and communication (RadCom) waveform design, we propose two technologies to deal with that. To be specific, we adopt Gray code technology to reduce the PMERP and simultaneously choose an optimal cyclic sequence to improve the PSLR of RadCom waveform. In our method, the optimal cyclic sequence is dynamically generated to continuously provide the best waveform according to the change of communication data. In addition, to meet the requirements of different radar detection tasks, two simple methods are utilized to adjust the bandwidth of RadCom waveform. To verify the advantages of the designed waveform, we conduct several simulation experiments to compare with some existing RadCom waveforms. The results show that our designed RadCom waveform can simultaneously achieve lower PMERP and higher PSLR. In addition, our designed RadCom waveform has a thumbtack type fuzzy function and shows the good ability to do multitarget detection.

Radar-Communication Integration Based on MSK-LFM Spread Spectrum Signal

At present, with the progress and innovation of technology, the radar communication dual function wave has become a hot research at home and abroad. Excellent integrated waveform can make full use resources of combat platform, reduce the size of equipment, and realize the actual functionality of the reality of the battle-field without affecting the radar communication func-tion. The MSK-LFM dual-function wave is a typical representative; it is based on LFM, through the MSK modulation to achieve the integration function. This paper proposes a scheme of combining the spread spectrum technology with the MSK-LFM waveform based on the previous literature. The simulation results show that the waveform envelope is more stable and the energy is more concentrated. With the introduction of spread-spectrum technology, the new waveform ambiguity function graph is much closer to the thumbtack than the traditional MSK-LFM waveform.