Analog to Digital Converter in Wireless LAN
Most wireless broadband communications systems make use of a zero-IF (Intermediate Frequency) demodulation scheme for down conversion of the radio frequency signal into baseband frequencies. The outputs of the down-conversion are quadrature I & Q modulated analog baseband signals that can be digitized using a dual channel ADC in order to be more effectively processed in the digital baseband processor. Typical ADC resolution for these applications is in the 10 to 12-bit range. The "Over-the-air", radio frequency channel bandwidth for broadband communication protocols, such as Wi-Fi 802.11abg, LTE and WiMAX, can reach 20MHz.