evidence: In the 1980s, the U.S. military began looking for ways to update its battlefield communications network. Challenges faced by Soldiers on the ground during early Cold War-era conflicts in Korea and Vietnam had exposed shortcomings in the force’s terrestrial radio system. The Army needed a replacement that offered enhanced range, better error correction, data capability, and the ability to automate call routing and switching, which would allow signal operators to manage more users at once. A massive research effort yielded the first major leap in field communications since the World War II crystal radio—Mobile Subscriber Equipment or MSE, the precursor to the modern mobile phone.