Background and Introduction
We live in a world that is increasingly connected and where the need for wireless communications is omnipresent. The range of RF applications is growing rapidly with everything from wearables to smart home appliances requiring reliable, wireless connectivity. As a result of this, the number of standards for air interfaces is also increasing quickly, some would say to the point of excess. Do we really need all of these standards or alliances and is there enough market share to enable them all to thrive or even survive?
The more traditional professional RF markets of wireless data, satellite communications, avionics and marine, plus scientific, medical and industrial also require radio networks which has helped to drive the ubiquity of 2.4 GHz wireless, most prominently those deploying Wi-Fi and Bluetooth ‘standards’. In addition, the lower radio spectrum remains highly active and diverse in its applications for HF, VHF and UHF systems some of which is now occupying bands previously used for terrestrial broadcasting
Implementing wireless capability in new product design has become a high-pressure business with the requisite short time-to-market making the demands on the RF designer ever more daunting. The traditional approach of discrete design to realise radio functions is becoming quickly dismissed as the need to deliver a plethora of RF capable products prevails. RF engineers need silicon radio suppliers who are expert in the design and supply of low-power analogue, digital and mixed-signal semiconductors. There is also a need to deliver a range of modular building blocks for implementation as either a partial or complete ‘wireless front end’.
Flexible and high-performance integrated circuits are required for HF, VHF and UHF designs which enable engineers to adopt a building-block method for their RF design needs. In summary a design approach that incorporates versatile, low-power and well-supported RF building-block helps wireless design teams to speed their design cycle and get their companies’ products in to the market ahead of the competition.
Challenging RF Applications
Some engineers still choose to use discrete devices for their RF design methodology. However, this is at odds with the commercial pressures that they face to get products into the market quickly and efficiently thus helping to give their companies’ the best chance to gain market share. These factors are driving significant change in wireless designs.
There is an evolution of wireless networks for ever increasing data rates and capacities. A prime example of this is Wi-Fi and Bluetooth networks as these applications are becoming one of the dominant drivers for semiconductor development. There are many challenges for current design techniques e.g. (ultra-) low power consumption. The rapid growth of wireless networks increases the need for highly integrated and low-cost solutions. Fast-growing markets, the proliferation of applications and increased levels of competition all increase the demand for very short development cycles.
Consequently, new design practices for wireless systems are imperative and a new, better-adapted approach for RF design has emerged. Based on the principles of platform-based design, it features RF building blocks with higher levels of reusability and early consideration of system performance.
The wireless receiver is a good example of how these design techniques work. The receiver is a complex system traditionally realised with separate system design and discrete circuits. Deploying the building-block design approach reconciles several challenges in the realisation of such RF sub-systems.
With its headquarters in the UK, CML Microcircuits is a world leader in delivering RF building-block solutions that are ideally suited to a diverse range of RF applications. The building blocks of CML’s devices for such designs typically include the following elements:
Receiver (Rx), Transmitter (Tx), Transceiver (XCVR), Power amplifier (PA), Mixer, Local Oscillator (LO), Voltage-Controlled Oscillator (VCO) and Phase-Locked Loop (PLL).
These commonly required functions comprise the key features required to quickly build complex wireless designs with the advantage of ready commercial availability and a support infrastructure that will further speed the design cycle and so help to reduce the pressure on RF design engineers.
The following are the key benefits and advantages of using a building-block or modular approach to RF design, as opposed to the use of discrete components and circuits. They can be summarised as follows:
- Shorter design cycle.
- Faster time-to-market and reduced time-to-money.
- Simpler testing of the finished design.
- Fewer components required to complete the design.
- Higher reliability.
- Enhanced performance
- Better control of tolerances.
- Lower-cost end products.
While the use of discrete components can offer some applications a greater degree of flexibility, in most cases the use of integrated building blocks will yield some if not all of the above list of benefits. The technology and products delivered by CML Microcircuits are ideally adapted to this approach to RF design.