What is a single sideband mixer?

What is a single sideband mixer?

Single Sideband (SSB) mixers allow a user to upconvert a signal onto a carrier while suppressing the same image frequency signal, relaxing transmitter filter requirements.

How image rejection mixer works?

In order to be able to operate, image reject mixers, image rejection mixers utilise the phasing techniques to cancel out the unwanted mix products. To achieve this an image reject mixer utilises two balanced mixers and the quadrature (90°) hybrids as shown below.

How does IQ mixer work?

An IQ-mixer consists of two balanced mixers and two hy- brids. It provides two IF signals with equal amplitudes which are in phase quadrature. These devices play an in- creasing role in the processing of high-frequency signals, especially as modulators and demodulators.

What is a sideband signal?

In electronic signal transmission, a sideband is the portion of a modulated carrier wave that is either above or below the basic ( Baseband ) signal. The portion above the baseband signal is the upper sideband ; the portion below is the lower sideband .

What is single sideband suppressed carrier modulation?

Single-sideband Suppressed Carrier (SSB-SC) modulation is a technique where the carrier is modulated to produce only a single sideband (either upper or lower) at modulation frequency away from carrier while simultaneously suppressing the carrier, i.e. frequency shifting/conversion.

How can an image rejection frequency be suppressed?

The image spectrum can be suppressed via filtering, but the filtering approach to image rejection involves an important design trade-off and prevents monolithic integration.

What is a good image rejection ratio?

Image rejection ratio IMRR is measured in dB, giving the ratio of the wanted to the unwanted signal to yield the same output from the receiver. In a good design, ratios of >60 dB are achieveable.

What are sidebands Why are they important?

In radio communications, a sideband is a band of frequencies higher than or lower than the carrier frequency, that are the result of the modulation process. The sidebands carry the information transmitted by the radio signal. The sidebands comprise all the spectral components of the modulated signal except the carrier.

What is the disadvantage of SSB filters?

Disadvantages of SSB over full carrier DSB wave The generation of SSB requires sharp cut off characteristics of the sideband suppression filter. SSB receivers require carrier recovery and synchronization circuit which adds to their cost, complexity and size.

Why is IQ modulation used?

What’s an IQ Modulator? An IQ modulator is a device that converts baseband information into RF signals. Internally, two double-balanced mixers are combined as shown below. By modulating with both in-phase (I) and quadrature (Q) inputs, any arbitrary output amplitude and phase can be selected.