First installment of 'Traveling Japan with WiFi in hand: Reiwa Ino Tadataka Project' launches! Real-world connectivity test on Tanegashima: Rakuten Mobile survives in caves when others fail

Takahiro Araki, supervisor of All-Connect Magazine (operated by ALL CONNECT), has launched a series of field connectivity tests titled "Traveling Japan with WiFi in hand: Reiwa Ino Tadataka Project."

For the first installment, four networks—Starlink, Rakuten Mobile, and two types of WiMAX devices—were simultaneously tested at six locations on Tanegashima, Kagoshima Prefecture. The results showed that Rakuten Mobile was the only service to maintain connectivity inside a remote cave.

The project stems from the discrepancy between carriers' official population coverage statistics and actual field performance. Araki, with experience in both the travel and telecom industries, is publishing this independent data gathered through his own field research.

Survey Overview: - Date: May 22, 2026 - Location: Tanegashima, Kagoshima Prefecture - Networks Tested: Rakuten Mobile, Starlink, WiMAX (NC03, DOCK)

Key Findings: 1. WiMAX services are largely out of range outdoors in remote islands, though effective in urban areas. 2. Rakuten Mobile achieved zero "out of range" spots, proving its capability on remote islands. 3. Starlink is most powerful in open spaces but has limitations for indoor use.

Tentative Guidelines for Use: - While moving/walking: Rakuten Mobile - For work at base: Starlink - For supplementary use in urban areas: WiMAX