價格：免費
檔案大小：21.3 MB
版本需求：需要 iOS 8.1 或以上版本。與 iPhone、iPad 及 iPod touch 相容。
支援語言：英語
The acoustic transmitter app is designed for use with hands-on guided learning explorations in digital communication and signal processing. The app provides a digital communication transmission signal modulated to an acoustic carrier frequency.
The acoustic transmitter app can be operated in two modes: carrier tone and text transmission. In carrier tone mode, the app simply transmits the waveform cos(2πfct) for a 400 millisecond duration at a user-specified carrier frequency, fc < 22.05 kHz. In the text transmission mode, the app provides a digital communication transmission modulated to a programmable acoustic carrier frequency. The transmitter implements quadrature amplitude modulation, a 13-symbol Barker code for timing and frequency recovery, and a data payload fixed at 50 ASCII characters.
支援平台：iPhone, iPad