調頻是指讓高頻振蕩的頻率隨著音頻信號大小而變化。
調頻無線技術的原理和收音機工作原理比較接近，使用的是FM（調頻）方式。不過收音機的調頻使用的是模擬信號，相對而言失真比較明顯，采用調頻無線技術的音響多數使用數字方式。簡單的說是將模擬音頻信號通過AD轉換器轉換為數字信號，再將信號對載波進行調制並發射，接收端則使用同樣頻率接收，通過DA轉換器轉換為模擬信號，然後放大輸出到揚聲器。載波是無線發射器的中心頻率，FM調制就是指用聲音信號對載波波形的頻率參數進行控制，使載波信號帶有聲音信息。
調頻無線技術比較成熟，實現的成本比較低。其缺點是無線電波容易受到幹擾，當周圍有頻率比較接近的無線電波時會產生明顯的失真。為避免這種情況，音響的無線調頻載波頻率非常高，遠遠高於無線廣播的載波頻率，有些產品還可以手工設定數個不同載波頻率，以避免同類設備之間的幹擾。
翻譯之後：
FM frequency modulation
FM refers to let high-frequency oscillation frequency with the changes in the size of the audio signal.
FM wireless technology and the principles of operating principle is closer to the radio, using FM (frequency modulation) mode. However, the FM radios used by the analog signal is relatively more obvious distortion using FM radio technology, the majority of the use of digital audio. Simply put, is the analog audio signal through the AD converter into a digital signal, and then to the carrier signal modulation and launched the receiving end is using the same frequency to receive, through the DA converter for converting analog signals, and then zoom to the speaker output. Carrier is a wireless transmitter at the center frequency, FM modulation refers to the use of the voice signal to the carrier wave frequency control parameters so that the carrier signal with a voice message.
FM wireless technology more mature and realize the cost is relatively low. The shortcoming of radio waves is vulnerable to interference, when surrounded by close to the frequency of the radio wave will have a significant distortion. To avoid this situation, the wireless FM audio carrier frequency is very high, much higher than the carrier frequency of the radio, some products can also be manually set up several different carrier frequency to avoid interference between similar devices.