Highfrequency (HF) communications play an important role in the field of their communications because of their skywave propagation characteristics.
短波通信由于其天波传播特性,在通信领域具有其它通信手段无法替代的地位。
2
In terms of operation frequency, RFID systems can be divided into four categories: low frequency (LF), highfrequency (HF), ultra highfrequency (UHF), and microwave.
根据工作频率来分,RFID系统可以分为低频,高频,超高频和微波四个波段。
3
MHFCS has the capability to transform highFrequency (HF) communications worldwide and provides nations with the highest levels of global connectivity while enhancing their information security.