To prevent battery drain, 3GPP generally mandates that while under international roaming, a cellular device only scan for networks of the foreign country. For example, a US-based cellular device that is roaming in Canada will not generally scan for US service providers so long as it is being served by a Canadian service provider. This sometimes results in the unintended consequence of a cellular device in a border area physically in the home country but nevertheless stuck in international roaming.
Techniques of this disclosure provide a mechanism for a cellular device to recognize, through a process of self-learning, its presence in a border region. When a cellular device finds itself in a border region, it intelligently scans for preferred carriers in both home and foreign countries. When not close to a border region, the cellular device scans exclusively for carriers of the country it is currently physically present in.
Nayak, Shivank, "Cell selection in border regions", Technical Disclosure Commons, (November 22, 2017)