Power-Aperture Product Resource Allocation for Radar ISAC

This article deals with the problem of power aperture product (PAP) management in a multifunction phased array radar (MPAR) performing sensing in both line of sight (LOS) and non line of sight (NLOS), and communications. To this end, two different quality metrics are introduced, namely the range where the cumulative detection probability (for sensing) and the channel capacity per bandwidth (for communications) attain a specified value. Then, suitable utility functions are defined to map the quality index relative to the corresponding perceived utility for each task. The resource allocation is hence formulated as a constrained optimization problem whose solution optimizes the global radar quality of service (QoS). The method is finally validated by means of numerical simulations

A survey of new technology for cockpit application to 1990's transport aircraft simulators

Two problems were investigated: inter-equipment data transfer, both on board the aircraft and between air and ground; and crew equipment communication via the cockpit displays and controls. Inter-equipment data transfer is discussed in terms of data bus and data link requirements. Crew equipment communication is discussed regarding the availability of CRT display systems for use in research simulators to represent flat panel displays of the future, and of software controllable touch panels

Technical Workshop: Advanced Helicopter Cockpit Design

Information processing demands on both civilian and military aircrews have increased enormously as rotorcraft have come to be used for adverse weather, day/night, and remote area missions. Applied psychology, engineering, or operational research for future helicopter cockpit design criteria were identified. Three areas were addressed: (1) operational requirements, (2) advanced avionics, and (3) man-system integration

Assessment of cockpit interface concepts for data link retrofit

The problem is examined of retrofitting older generation aircraft with data link capability. The approach taken analyzes requirements for the cockpit interface, based on review of prior research and opinions obtained from subject matter experts. With this background, essential functions and constraints for a retrofit installation are defined. After an assessment of the technology available to meet the functions and constraints, candidate design concepts are developed. The most promising design concept is described in detail. Finally, needs for further research and development are identified

Power-Aperture Resource Allocation for a MPAR with Communications Capabilities

Multifunction phased array radars (MPARs) exploit the intrinsic flexibility of their active electronically steered array (ESA) to perform, at the same time, a multitude of operations, such as search, tracking, fire control, classification, and communications. This paper aims at addressing the MPAR resource allocation so as to satisfy the quality of service (QoS) demanded by both line of sight (LOS) and reflective intelligent surfaces (RIS)-aided non line of sight (NLOS) search operations along with communications tasks. To this end, the ranges at which the cumulative detection probability and the channel capacity per bandwidth reach a desired value are introduced as task quality metrics for the search and communication functions, respectively. Then, to quantify the satisfaction level of each task, for each of them a bespoke utility function is defined to map the associated quality metric into the corresponding perceived utility. Hence, assigning different priority weights to each task, the resource allocation problem, in terms of radar power aperture (PAP) specification, is formulated as a constrained optimization problem whose solution optimizes the global radar QoS. Several simulations are conducted in scenarios of practical interest to prove the effectiveness of the approach

Relative Entropy-Based Waveform Optimization for Rician Target Detection with Dual-Function Radar Communication Systems

In this paper, we consider waveform design for dualfunction radar-communication systems based on multiple-inputmultiple-out arrays. To achieve better Rician target detection performance, we use the relative entropy associated with the formulated detection problem as the design metric. We also impose a multiuser interference energy constraint on the waveforms to ensure the achievable sum-rate of the communications. Two algorithms are presented to tackle the nonlinear non-convex waveform design problem. In the first algorithm, we derive a quadratic function to minorize the objective function. To tackle the quadratically constrained quadratic programming problem at each iteration, a semidefinite relaxation approach followed by a rank-one decomposition procedure and an efficient alternating direction method of multipliers (ADMM) are proposed, respectively. In the second algorithm, we present a novel ADMM algorithm to tackle the optimization problem and employ an efficient minorization-maximization approach in the inner loop of the ADMM algorithm. Numerical results demonstrate the superiority of both algorithms. Moreover, the presented algorithms can be extended to synthesize peak-to-average-power ratio constrained waveforms, which allows the radio frequency amplifier to operate at an increased efficiency

Multicodes for improved range resolution in radar

Third generation (3G) wireless systems are required to support a variety of communication services like voice, image, motion picture transmission, etc, each of which requires different transmission rates. Multi-code modulation has been introduced therefore as a means of supporting multi-rate services and operating in multi-cell environments [8, 9, 10]. This multi-rate multi-function capability may be used in Radar related applications, too. For example, a single transmitted waveform consisting of two orthogonal codes can be used to simultaneously track a target and obtain high range resolution. Tracking requires low bandwidth and high resolution needs a high bandwidth signal. Orthogonal codes like Walsh codes can be used to provide multiple rates if the codes are chosen from the same matrix, because certain Walsh codes of the same length have very different bandwidths. Therefore, as an extension to its use in communication, multi-codes can be used to enable multi-function operations in a Radar system. The first criterion for choosing a Radar waveform, whether single or multi-code, is its resolving capability in range and Doppler. A measure of range resolution or sensitivity to delay commonly used in Radar literature is the Peak to Sidelobe Level Ratio (PSLR) of the code\u27s autocorrelation function. The multi-codes proposed in this work are found to have better (lower) PSLRs than existing radar codes when the number of simultaneously transmitted codes is large. In the special case of using an entire set of orthogonal codes of any length, the resulting multi-code consists of just a single pulse of thickness equal to the chip width of the code used. This pulse will have a \u27perfect\u27 autocorrelation function with only a single peak at the main lobe and zero sidelobes. This gives the ideal PSLR for radar purposes. An important aspect of using multi-codes in Radar is the need for multiple transmitters to avoid the high peak factor that would result if only a single antenna 15 used. This requires the Radar system to have multiple transmitters as in phased array radar. The best example is a multi-function digital array radar that transmits a unique orthogonal code from each of its antenna elements as described by Rabideau and Parker in [13]. The system described in this publication makes use of the array mode of operation of the Radar to transmit orthogonal codes from each antenna element which are then phased and combined at the receiver. The phase (or angle) of the signal at each receive antenna element can be used to better resolve targets that are spatially separated. This thesis introduces the concept of multicodes in Radar. Further, the advantages of using multiple coded waveforms over the known Radar polyphase codes are demonstrated by simulations

Power-Aperture Resource Allocation for a MPAR with Communications Capabilities

Multifunction phased array radars (MPARs) exploit the intrinsic flexibility of their active electronically steered array (ESA) to perform, at the same time, a multitude of operations, such as search, tracking, fire control, classification, and communications. This paper aims at addressing the MPAR resource allocation so as to satisfy the quality of service (QoS) demanded by both line of sight (LOS) and non line of sight (NLOS) search operations along with communications tasks. To this end, the ranges at which the cumulative detection probability and the channel capacity per bandwidth reach a desired value are introduced as task quality metrics for the search and communication functions, respectively. Then, to quantify the satisfaction level of each task, for each of them a bespoke utility function is defined to map the associated quality metric into the corresponding perceived utility. Hence, assigning different priority weights to each task, the resource allocation problem, in terms of radar power aperture (PAP) specification, is formulated as a constrained optimization problem whose solution optimizes the global radar QoS. Several simulations are conducted in scenarios of practical interest to prove the effectiveness of the approach.Comment: 12 pages, 14 figure

Identification of high-level functional/system requirements for future civil transports

In order to accommodate the rapid growth in commercial aviation throughout the remainder of this century, the Federal Aviation Administration (FAA) is faced with a formidable challenge to upgrade and/or modernize the National Airspace System (NAS) without compromising safety or efficiency. A recurring theme in both the Aviation System Capital Investment Plan (CIP), which has replaced the NAS Plan, and the new FAA Plan for Research, Engineering, and Development (RE&D) rely on the application of new technologies and a greater use of automation. Identifying the high-level functional and system impacts of such modernization efforts on future civil transport operational requirements, particularly in terms of cockpit functionality and information transfer, was the primary objective of this project. The FAA planning documents for the NAS of the 2005 era and beyond were surveyed; major aircraft functional capabilities and system components required for such an operating environment were identified. A hierarchical structured analysis of the information processing and flows emanating from such functional/system components were conducted and the results documented in graphical form depicting the relationships between functions and systems