Military

Self-Healing Minefield

The Self-Healing Minefield is an antitank landmine system that does not rely on antipersonnel landmines for dismounted breach protection. Instead the Self-Healing Minefield employs a novel breach response mechanism that can determine both mounted and dismounted enemy assaults on the minefield and respond to maintain obstacle integrity. Contrary to the current mixed minefield systems (Volcano, RAAM/ADAM, and Gator) which require antipersonnel landmines co-located with an antitank minefield to complicate dismounted breaching of the antitank minefield, the Self-Healing Minefield employs intelligent, mobile antitank mines alone to defeat all enemy breaching.

The Self-Healing Minefield system is designed to achieve an increased resistance to dismounted and mounted breaching by adding a novel dimension to the minefield. Instead of a static complex obstacle, the Self-Healing Minefield is an intelligent, dynamic obstacle that responds to an enemy breaching attempt by physically reorganizing. The Self-Healing Minefield consists of surface scattered antitank mines that can detect an enemy attack of the minefield and respond autonomously, by having a fraction of the mines move to heal the breach. Since the minefield is no longer a static obstacle, an open breach cannot be maintained. The Self-Healing Minefield forces the enemy to attack the minefield and deplete the antitank mines surrounding the breaching lane by either repeated assaults or a wide area breach/clearance. In either case the enemy has increased their exposure to covering fires when compared to the current mixed system minefield. An ongoing modeling effort indicates that a self-healing minefield will provide greatly increased military effectiveness of the obstacle.

Los Alamos National Laboratory has developed a model warhead for the antitank mines in the Self-Healing Minefield (SHM). The DARPA concept of the Self-Healing Minefield requires that the mines to move to fill gaps when it is determined necessary by collective processing of sensor information communicated amongst the mines. The application of advanced technology in the mine required by the mobility and communication systems justifies the application of advanced technology for the warhead to minimize, or at least reduce, the warhead allowances necessary. The SHM model warhead has, to date, met or exceeded initial performance requirements (fielded capability) while maintaining attractive volume and weight characteristics. The positive design and testing results, combined with the existence of sophisticated on-board electronics, suggests that it is possible to enhance the capability of the warhead system. Such enhanced capability is quantified by increased vehicle kill probability given an encounter. Liberal use of embedded initiation points controls detonation wave propagation. The control is applied to improve the efficiency of the coupling of the explosive to the liner, as do inert wave shapers, and to open a multimode pathway to address track defeat or the defeat of other vehicles

The SHM uses radio links as the primary mode of communication between mines. Following network setup, each node transmits periodic signals to indicate its status to the rest of the network. The absence of expected transmissions from one or more mines is one of the main indicators used to identify and locate breach attempts. Remaining mines use their radio links to inform more distant mines of the breach attempt, and to coordinate the response. The SHM may also communicate with a remote controller via a reach-back option.

Mine-to-mine radio links are short range. Their low transmit power, wide-beam antennas, and low antenna height, make them susceptible to jamming by an attacker. The SHM has a multi-layered response to jamming. If radio jamming is successful, the network can maintain connectivity at lower data rates via acoustic links. If acoustic links are jammed, the network enters the autonomous response mode, which will maintain minefield integrity for several more hours. However, minefield integrity during repeated breach attempts will be maintained longest if radio communications are available. The SHM radio network uses spread-spectrum communication techniques, with robust protocols and reconfigurable networks, to minimize jamming sensitivity. Lincoln Laboratory is looking at improvements to the SHM waveform and SHM receivers, to provide even more robust radio links.

A jamming threat model has been developed based on the state-of-the-art in radio electronics and deployment strategies ranging from a large, truck-borne mobile jammer, to a large number of small "distributed" jammers scattered over the minefield. The threat model includes "smart-jamming" techniques such as frequency following, time following, and focused attacks on network control data. The threat model is used to evaluate the effectiveness of different measures that can be taken to improve network robustness. Measures under consideration include increased processing gain, adaptive modulation, increased waveform randomization, adaptive frequency hopping, time-domain interference cancellation, and adaptive array processing. Large distributed antenna arrays are being investigated for reach-back/reach-forward communications. Each array consists of multiple mines with coordinated transmission and receiver processing via the SHM network. Arrays have the ability to implement beamforming and directional interference cancellation.

The Self-Healing Minefield program is a 3-year effort focused on the development and demonstration of the key enabling technologies necessary in a mobile, intelligent, networked antivehicle mine system. The program plan establishes a two-phased approach where the first 2 years focus on the subsystem development and a small-scale integrated test. The second phase is focused on refinement of the technologies and scaling to a tactically significant field text. The program completed Phase I in March 2002 and is aggressively pursuing the overall program objectives in Phase II. Upon completion of Phase II the Self-Healing Minefield will be positioned to transition to the U.S. Army for continued development.