A method for timing sensing of localization signals by an in-vivo device comprising a timing unit, the method comprising: defining, by the timing unit, a work cycle of the in-vivo device, the work cycle including a sensing window during which the in-vivo device is configured to receive localization signals, the timing unit timing the work cycle using a clock signal and defining within the work cycle a reference time; operating the in-vivo device during the work cycle to: (i) transmit a data frame from the in-vivo device to an external receiver, the data frame comprising data enabling generation by the external receiver of a synchronization signal for an external localization signals source based on the clock signal, the reference time, and on time specifics of the sensing time window; (ii) measure time elapsing from the reference time by using the clock signal; (iii) sense, based on the elapsed time, during a time period complying with the time specifics of the sensing time window, one or more localization signals transmitted to the in-vivo device by the external localization signals source at times and for durations specified by the synchronization signal, the synchronization signal to cause the external localization signals source to transmit only during a time period overlapping with the sensing window of the work cycle of the in-vivo device; and producing, by the in-vivo device, localization data from the sensed localization signals. defining, by the timing unit, a work cycle of the in-vivo device, the work cycle including a sensing window during which the in-vivo device is configured to receive localization signals, the timing unit timing the work cycle using a clock signal and defining within the work cycle a reference time; operating the in-vivo device during the work cycle to: (i) transmit a data frame from the in-vivo device to an external receiver, the data frame comprising data enabling generation by the external receiver of a synchronization signal for an external localization signals source based on the clock signal, the reference time, and on time specifics of the sensing time window; (ii) measure time elapsing from the reference time by using the clock signal; (iii) sense, based on the elapsed time, during a time period complying with the time specifics of the sensing time window, one or more localization signals transmitted to the in-vivo device by the external localization signals source at times and for durations specified by the synchronization signal, the synchronization signal to cause the external localization signals source to transmit only during a time period overlapping with the sensing window of the work cycle of the in-vivo device; and (i) transmit a data frame from the in-vivo device to an external receiver, the data frame comprising data enabling generation by the external receiver of a synchronization signal for an external localization signals source based on the clock signal, the reference time, and on time specifics of the sensing time window; (ii) measure time elapsing from the reference time by using the clock signal; (iii) sense, based on the elapsed time, during a time period complying with the time specifics of the sensing time window, one or more localization signals transmitted to the in-vivo device by the external localization signals source at times and for durations specified by the synchronization signal, the synchronization signal to cause the external localization signals source to transmit only during a time period overlapping with the sensing window of the work cycle of the in-vivo device; and producing, by the in-vivo device, localization data from the sensed localization signals.