Devices and methods are disclosed for generating, filtering, and amplifying signals that are sent and received using SOCs. These improved methods and devices advantageously provide filtering of composite RF signals such that the RF signals can be transmitted with an improved SNR. Such filtered signals can then be transmitted at a higher power. Because filtering is performed at an intermediate frequency, the higher cost of low-noise RF-transmitters and/or RF filtering components can be avoided. Accordingly, less expensive (e.g., noisier) components, such as readily available wireless transceiver SOCs, can be used for generating RF signals, filtering the signals, and then transmitting the filtered signals at higher power. As a result of these devices and methods, inexpensive SOCs may be used at higher powers and over longer ranges than would be normally expected.

There is provided an apparatus and a method for the receipt and processing of data signals carried in a plurality of predefined frequency bands and allowing a frequency band required at an instant of time to be selected from the predefined frequency bands from which data is to be retrieved. Passing the data signals from the wanted band to a transmitter and/or receiver including first and second mixing means to process the data signals, typically using in-phase and quadrative data feeds to create a predefined representation of the wanted frequency band, to provide an output for receipt by at least one broadcast data receiver and at least the transmitter and/or receiver is provided as part of an integrated circuit rather than as separate connected components.

An integrated multi-channel photonic radio-frequency (RF) receiver system includes a master oscillator including a laser source configured to generate laser light. A local oscillator (LO) path may include an LO generator, an LO modulator, an optical LO filter, and an optical amplifier optically coupled to one another to generate an LO signal. Multiple RF-modulation channels are coupled through an optical switch to a number of channel filters and configured to produce a number of filtered RF-modulated optical signals. An optical combiner may combine the LO signal with each filtered RF-modulated optical signal to generate down-converted optical signals. Each channel of the plurality of RF-modulation channels includes a channel laser coupled to a channel modulator, and the LO generator and channel lasers of the RF-modulation channels are fed by the laser light of the master oscillator.

A sub-harmonic mixer two or more cascaded stages for converting a Radio Frequency signal to an Intermediate Frequency signal. Each stage comprises a common-emitter transistor or a common-source transistor and each stage having an input and an output, the output of each stage is coupled to the input of a next stage by a capacitor. An Alternating Current choke is coupled at a collector or drain of each transistor. An LO input is coupled to the input of a first stage of the two or more stages; an RF input is coupled to the output of the first stage of the two or more stages; and an IF output is coupled to the output of a last stage of the two or more stages.