The Australian Communications and Media Authority has seen a steady increase in complaints about interference to mobile phone networks.
Figures released in the ACMA's annual report (pdf) show mobile interference complaints have risen steadily over the past three years, from 211 in 2009-10 to 238 in 2010-11, and 255 complaints in 2011-12.
Telcos including Telstra have expressed concerns in recent months about the number of illegal repeaters being used in Australia to boost signals — at the expense of other users in a mobile cell.
The ACMA indicated last month that it intended to crack down on illegal repeater use, as it has done — and continues to do — with illegal mobile phone jammers.
Australian mail authorities intercepted 179 illegal mobile phone jammers over the past financial year, a slightly smaller haul than 185 devices seized in 2010-11.
As with prior years, intended recipients of an illegal device were sent a letter instead warning "that the device they purchased online from an overseas retailer was prohibited and had been forfeited to the Commonwealth".
There has been only one ACMA-sanctioned test of jamming technology in recent years.
The NSW Department of Correctional Services last year conducted laboratory tests of a system it hopes to deploy at Lithgow jail to prevent illegal use of mobile phones at the facility.
Although the ACMA noted in its 2010-11 annual report that "consideration of regulatory arrangements" for a field trial of the jamming technology at Lithgow was expected to occur in "late 2011 or early 2012", the authority noted in its 2011-12 annual report that a proposed field trial would now commence in January 2013.