Two OFDM radar algorithms (the Maximum Likelihood and a MUSIC-based algorithm) are introduced and their fundamental limits concerning accuracy are explained. To simplify the analysis, we research the special case of only one target in the radar's detection range, which facilitates the individual effects on the estimation quality. Through simulations, we can show that OFDM radar works well for this case.

Since traditional radar signals are “unintelligent,” regarding the amount of information they convey on the bandwidth they occupy, a joint radar and wireless communication system would constitute a unique platform for future intelligent transportation networks effecting the essential tasks of environmental sensing and the allocation of ad-hoc communication links, in terms of both spectrum efficiency and cost-effectiveness. In this paper, approaches to the design of intelligent waveforms, that are suitable for simultaneously performing both data transmission and radar sensing, are proposed. The approach is based on classical phase-coded waveforms utilized in wireless communications. In particular, requirements that allow for employing such signals for radar measurements with high dynamic range are investigated. Also, a variety of possible radar processing algorithms are discussed. Moreover, the applicability of multiple antenna techniques for direction-of-arrival estimation is considered. In addition to theoretical considerations, the paper presents system simulations and measurement results of complete “RadCom” systems, demonstrating the practical feasibility of integrated communications and radar applications.

We analyse mobile propagation channels which occur in the context of car-to-car communications in the 24~GHz ISM band. From the information gathered, we design robust frame designs for combined radar and communication systems using high-bandwidth OFDM signals. Two solutions are proposed: the combination of a spread spectrum technique and a standard convolutional encoder, as well as a low rate Reed-Muller code. We can show that while both perform well enough for the channels analysed, the Reed-Muller code has some advantages for the RF system, but achieves lower data rates.

This paper evaluates multiple antenna systems in realistic Car-to-Car (C2C) communication channels for urban intersection scenarios. With a three-dimensional ray-tracing simulation tool the channel characteristics are determined for various antenna positions and numbers of antennas. The results clearly show the advantage of multiple antenna systems. Suitable antenna positions are determinedthatallowtheoptimizationofthe channel capacity ( )However, in spite of the benefits of route specific infor- mation, the amount of data to be processed and transmitted presents a great challenge. Other road users as well as the surroundings influence the channel in a complex manner. It follows that a detailed knowledge about the inter-vehicle trans- mission channel is necessary for the design and optimization

The design process of a joint radar and communication system employing OFDM is analyzed. In particular, the question on how to choose OFDM modulation parameters such as carrier distance, guard interval length, frame length or pilot design is studied. Such systems use the same OFDM frames to transmit data and image the surroundings, so both radar and communication are affected by the choice of these parameters. The main design criteria for the radar component are accuracy of distance and speed measurements, whereas the communication subsystem needs to be designed such that it transmits robustly through a mobile communication channel. As these design criteria often are antipodal, arguments for choosing a particular set of modulation parameters are discussed. The presented design process is applied to the case of a vehicular (car-to-car) communication, in which moving participants communicate in the 24 GHz range.

In this paper the possibility of designing an OFDM system for simultaneous radar and communications operations is discussed. A novel approach to OFDM radar processing is introduced that overcomes the typical drawbacks of correlation based processing. A suitable OFDM system parameterization for operation at 24 GHz is derived that fulfills the requirements for both applications. The operability of the proposed system concept is verified with MatLab simulations.

Basic principles for ultra-wide-band (UWB) radiation are presented and discussed in this paper. The discussion starts with a description of the influence of antennas on UWB transmission. The parameters characterizing antennas in time and in frequency domain are specified. Since the number of possible antenna structures is nearly unlimited, the focus will be on a classification according to different radiation principles. For each of these mechanisms, the typical advantages and disadvantages are discussed, and an example antenna and its characteristics are presented. For a wireless engineer, the problem to solve is the proper design of an antenna with the desired radiation characteristics. The final outcome of this paper is that there exist numbers of UWB antennas, but not each of them is suited for any application, especially in view of radar and communication systems requirements.