Disaster-related mobile outage and congestion
災害時の通信障害・輻輳 saigaiji no tsūshin shōgai / fukusō
Loss or severe degradation of mobile service caused by damaged equipment, power or transmission links, or by unusually concentrated calling and data traffic after a disaster.
A base station can stop because the site, backhaul or power supply is damaged. Even intact equipment can become congested when many people call at once. Carriers may control ordinary traffic to protect emergency and other important communications.
Try text messages, carrier disaster message services and public Wi-Fi instead of repeated voice calls; keep the phone charged, download maps beforehand and follow official outage maps. An antenna icon does not guarantee that the network path beyond the base station is working.
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