基带
基带(英語:baseband)是频率范围非常窄的信号,也就是说幅度谱仅在原点(f = 0)附近才是非零的,其他频率几乎可以忽略。[1] 在电信与信号处理中,基带信号是未经载波调制的信号,即该信号的频率范围没有任何移位,[2] 而且频率很低 - 包含频带从接近 0 Hz到更高截止頻率或最大带宽。
![](http://upload.wikimedia.org/wikipedia/commons/thumb/9/92/Bandlimited2.svg/300px-Bandlimited2.svg.png)
由于基带信号是未经载波调制的信号,在GPS接收机和移动电话等无线数字通讯领域,基带信号有时也泛指已经过射频前端处理后的信号。[3][4]在无线通讯设备中,来自天线的信号先经射频前端的模拟电路接收,然后再转交给后续的数字电路进一步处理,而后者就是基带处理器。[3][4]在当前中文语境中,手机基带处理器所带的固件也简称“基带”[5]。
参见
编辑参考文献
编辑- ^ Leon W. Couch II. Digital and Analog Communication Systems. Prentice Hall. 1993.
- ^ B.P. Lathi. Modern Digital and Analog Communication Systems. Holt, Rinehart and Winston. 1983.
- ^ 3.0 3.1 Christian Piguet. 6: Low-Power Bandband Processors for Communications. Low-Power Processors and Systems on Chips. CRC Press. [2020-01-10]. (原始内容存档于2020-04-26).
Baseband Signals are all signals in a radio system, which are not modulated onto the carrier wave. In a cellular phone, this means all signals except those in the radio frequency (RF) part of the phone.
- ^ 4.0 4.1 U.S. International Trade Commission. In the Matter of Certain GPS Chips, Associated Software and Systems, and Products Containing Same, Investigation No. 337-TA-596 (报告). DIANE Publishing: 6.
A GPS receiver typically includes an analog signal processing portion in a radio-frequency circuit (an "RF Front End") and a digital signal processing portion in a baseband circuit (a "Baseband Processor"). In a GPS receiver, the RF Front End receivers the GPS signal, filters and amplifies the signal, and converts the resulting signal into a digital formbat. The resulting digital signal, which is sometimes referred to as the "baseband signal," is sent to the Baseband Processor.
- ^ 基带是什么. 太平洋IT百科. [2016-02-07]. (原始内容存档于2016-02-07).