Enhanced methods of cellular environment detection when interoperating with timed interfers

摘要

Techniques for performing analysis of a cellular telephone signaling environment in the presence of interferers. The techniques do the analysis by employing a receiver to listen to the cellular environment during holes in the interference. The holes have a timing which differs from that used by the cellular telephone signaling environment and will thus over time overlap with structures of interest in the cellular telephone environment. The holes may be smaller than the structure of interest. The signals which the receiver hears in the holes are analyzed and combined to reproduce the structure. The combination may involve statistical methods and weighted decoding. The analysis obtains information which permits surgical attacks on individual wireless devices which are in the traffic state. Example applications of the techniques are given for the GSM and CDMA cellular telephone standards.

主权项

1. A method of obtaining information about a repeated structure in a signal which is generated according to the Global System for Mobile Communications (GSM) standard and which represents a sequence of symbols, the repeated structure having a first timing in the signal and the method being performed in apparatus including a receiver and a signal analyzer and comprising the steps performed in the apparatus of:
receiving the signal for a set of discrete periods in the receiver, the periods in the set having a second timing such that over a plurality of repetitions of the repeated structure in the signal, the entire repeated structure is received in the receiver, wherein, the set of discrete periods is made up of periods during which the signal is not being interfered with by an interferer; converting the signal as received in each of the discrete periods in the set into symbols; and analyzing the symbols in the analyzer to obtain the information about the repeated structure.