| 摘要 |
A multi-carrier radio system in which pairs of subcarriers are positioned in frequency such that each subcarrier in a pair is the image of the other subcarrier in the pair. By making each subcarrier the image of another subcarrier, the radio system of the present invention permits highly integrated low-IF transceiver implementation. In an exemplary embodiment, a multi-carrier transceiver includes an integrated receiver comprising a first mixer for mixing an input signal with a local oscillator signal to produce an in-phase downconverted signal. Additionally, a first phase shifter phase-shifts the local oscillator signal to produce a quadrature local oscillator signal, and a second mixer mixes the input signal with the quadrature local oscillator signal to produce a quadrature downconverted signal. Thereafter, a second phase shifter phase-shifts, or rotates, the quadrature downconverted signal to produce a rotated quadrature downconverted signal. A summer sums the in-phase downconverted signal and the rotated quadrature downconverted signal to produce an upper band detection output signal, and a subtractor subtracts the rotated quadrature downconverted signal from the in-phase downconverted signal to produce a lower band detection output signal. The exemplary multi-carrier transceiver also includes a compatible integrated transmitter for generating appropriate multi-carrier signals. |
