Disclosed herein is a multi-band ZigBee transceiver for supporting IEEE 802.15.4 wireless communications. In the multi-band ZigBee transceiver, a Multi-Mode Modem (MMM) selects any one of a European version standard using 860 MHz band, a US version standard using 920 MHz band, and a worldwide version standard using 2.4 GHz ISM band among IEEE 802.15.4 standards. A frequency synthesizing unit variably adjusts a carrier frequency according to the transmission standard. A transmission unit receives a digital modulated signal, low-pass-filters the digital modulated signal with a bandwidth thereof being variably adjusted, and up-converts the filtered digital modulated signal into an RF modulated signal corresponding to the selected transmission channel. A receiving unit down-converts the RF modulated signal into a BB modulated signal using the carrier frequency, low-pass-filters the BB modulated signal with a bandwidth thereof being variably adjusted according to the selected transmission standard, converts the filtered BB modulated signal into a digital modulated signal, and outputs the digital modulated signal to the MMM. A transmission/reception switch unit outputs the RF modulated signal, input from the transmission unit, to an antenna, or outputs the RF modulated signal, received from the antenna, to the receiving unit.

 
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