Advanced interference rejection and anti-jam methods for low power mobile battlefield communications

Mobile battlefield communication systems are called upon to operate effectively in increasingly adverse spectral environments. Obstacles to mobile battlefield communications include nonstationary command post co-site interference, ambient co-channel signals, and hostile jamming interferers. Typical interference levels encountered in a tactical environment can exceed the desired signal by 60 decibels. Such levels overwhelm the operational capabilities of current tactical radio systems. These conditions create a demand for anti-jam (AJ) radios that can survive nonstationary interference and maintain communications during mobility. We present interference rejection and anti-jam technologies for use in mobile, manpack, and handheld digital radios. Practical methods are presented that are within the capabilities of modern digital signal processors (DSPs). In contrast to interference mitigation techniques that require data rate reduction or added channel coding, methods are presented that improve the signal BER without sacrificing throughput. Near-term programmable architectures enable the introduction of these pre-processing functions for interference suppression. The complex arithmetic processor (CAP) is an example of emerging signal processors that are capable of “spectral awareness” and interference mitigation. Within a programmable architecture, signal processing techniques are presented that provide interference suppression for both hostile and ambient battlefield interference, including narrowband, partial-band, and co-site communication signal interferers