I-factor can be modeled when no analytical model is given for the receiver filter’s frequency response by estimating the filter by the TSM as in Figure 1a. When an analytical model is assumed for the receiver filter’s frequency response, the I-factor can be modeled without the need for receiver channel traces, as in Figure 1b. (a) Two DSSS signals shown together. The receiver filter may be estimated using a transmission on the receiver’s channel (channel 6 here, shown in red). The blue trace belongs to an interferer on the adjacent channel 7. (b) The receiver filter, in red, estimated as the DSSS TSM centered on channel 6 and the captured interferer DSSS signal, in blue, on channel 7, shown together.