FREMONT, CA: The primary challenge for the connected cars is the availability of sufficient electromagnetic spectrum for smooth and uninterrupted communication with other entities or better known as vehicle-to-everything (V2X) communications.
Conventionally, the transmitters and receivers are explicitly assigned electromagnetic spectrum in the form of frequency bands in a way that enables them a medium for wireless communication. But the range of the electromagnetic spectrum that is used for such communication comprises of a narrow range of frequency. In case of a high demand for the electromagnetic spectrum, it is impossible to accommodate all the communications among various connected entities. The shortage of electromagnetic spectrum is termed as spectrum scarcity.
In the case of V2X environment, spectrum scarcity is dangerous, especially when connected cars must have guaranteed access to the bandwidth. The access requirement can be for interchange safety information where several autonomous vehicles are operating. The interdependence of the entities requires guaranteed bandwidth available for each object.
Dynamic spectrum access (DSA) addresses the above challenge where it temporarily borrows the unused bandwidth frequency for seamless communication. The strength of DSA lies in its ability to exploit the electromagnetic environment for gaining access to the spectrum. The other implication is the efficient usage of the spectrum.
For connected V2X cars, DSA seeks out unused frequency bands for the exchange of critical information without the need to wait for a portion of the electromagnetic band. DSA incorporation is especially useful in case of an emergency such as accidents or other similar scenarios. In the case of conventional setup, such a situation will trigger all the connected vehicles and other on-road connected entities resulting in spectrum scarcity.
The cognitive radio or radio intelligence efficiently utilizes the spectrum and are also more flexible and versatile with an ability to adapt their functionalities based on external factors. Thus, cognitive radio plays a crucial role in using DSA for connected cars. Cognitive radio supporting DSA equips the connected vehicles with the intelligence to seek and utilize a frequency in case of spectrum scarcity.