A method for operating a multiple-mode multiple-band transceiver, the multiple-mode multiple-band transceiver comprising: a modulator for producing an analog signal in accordance with a selected communication protocol; a multiple-channel transmitter including a plurality of selectable transmit-channel components, the plurality of selectable transmit-channel components sharing at least one element coupled to an output of the modulator, the plurality of selectable transmit channel components forming at least first and second transmit channels configured to use a direct launch signal transmission technique to generate radio-frequency signals using at least a first multiple-access modulation technique comprising code division multiple access and a second multiple-access modulation technique comprising global system for mobile communication, wherein the first and second transmit channels traverse a dual-mode power amplifier that provides wideband band pass filtering for one of the transmit channels, and the modulator comprising a first low pass filter corresponding to an in-phase path of one of the first or second multiple access modulation technique, a second low pass filter corresponding to a quadrature path of the other of the first or second multiple access modulation technique, the first and second low pass filters being switched to accommodate the bandwidth of the selected communication protocol; wherein the method comprises: enabling, by a mode selector device configured to select a communication protocol, at least one of the first and second transmit channels to transmit a communication signal using one of the first and second multiple-access modulation techniques; and coupling the first transmit channel to an antenna via a duplexer, configured to pass wideband transmit and receive signals and via a switchplexer configured to selectively apply the first and second transmit channels to the antenna. a modulator for producing an analog signal in accordance with a selected communication protocol; a multiple-channel transmitter including a plurality of selectable transmit-channel components, the plurality of selectable transmit-channel components sharing at least one element coupled to an output of the modulator, the plurality of selectable transmit channel components forming at least first and second transmit channels configured to use a direct launch signal transmission technique to generate radio-frequency signals using at least a first multiple-access modulation technique comprising code division multiple access and a second multiple-access modulation technique comprising global system for mobile communication, wherein the first and second transmit channels traverse a dual-mode power amplifier that provides wideband band pass filtering for one of the transmit channels, and the modulator comprising a first low pass filter corresponding to an in-phase path of one of the first or second multiple access modulation technique, a second low pass filter corresponding to a quadrature path of the other of the first or second multiple access modulation technique, the first and second low pass filters being switched to accommodate the bandwidth of the selected communication protocol; enabling, by a mode selector device configured to select a communication protocol, at least one of the first and second transmit channels to transmit a communication signal using one of the first and second multiple-access modulation techniques; and coupling the first transmit channel to an antenna via a duplexer, configured to pass wideband transmit and receive signals and via a switchplexer configured to selectively apply the first and second transmit channels to the antenna.