Abstract :
One look at the radio spectrum allocation chart of any country is likely to show that most of the spectrum below 6GHz has already been allocated. This has given rise to the perception that radio frequency spectrum is in short supply. But, are we really running out of radio frequency spectrum? Analysis of intensity of radio spectrum usage over frequency, time and space by various groups in the United States and the UK has shown that in actuality, the radio spectrum is only used about 15% of the time on an average basis. IDA Singapore in collaboration with the Institute for Infocomm Research (I2R) has conducted a short study to look at the intensity of use of radio spectrum in Singapore. This study, which is by no means comprehensive, does give a snapshot of spectrum usage in a certain area of Singapore. Our measurement results show that the average spectrum utilization in the frequency band from 80MHz to 5.85GHz is below 5%. Furthermore, we can clearly see that certain bands are completely free because they are set aside because of cross-border spectrum coordination with our neighbouring countries. Given that the actual spectrum use intensity is relatively low in US, UK and now demonstrated, albeit on a sample basis in Singapore, it may be possible to explore the use of cognitive radio technologies to intensify the use of spectrum, provided it does not cause interference to the primary users.
