The performance is examined of a single-auxiliary-element adaptive sidelobe canceller (SLC) for multiple jammer environments. It is shown that multiple jammers can be equivalent to a single jammer for a single-auxiliary-element SLC system. This equivalence leads to an important result in that a single-auxitiary-element SLC system can reject multiple jammers. Computer simulations are given to confirm the theoretical analysis. © 1994 Taylor & Francis Ltd.