In Europe, most countries have national digital public safety networks in service, realised in a single harmonised band. Over time there has been a general convergence towards TETRA as the common open standard, but what will the users of tomorrow demand from these systems‾ The expectation is that wide-band data - enabling the transmission of high bandwidth services - will be a key driver for future networks. Is this really the case‾
Identifying future user requirements is critical to the long-term success of any network. Understanding if there is a real demand for cutting-edge services and high speed data, such as video streaming, is crucial. And if such services are required, how will they be delivered.
Options, options
While it is still early days, a number of solutions are being promoted as potential future networks.
- Multi-bearer data solutions - these are being used with TETRA networks today and it is credible that these could be further developed to include broadband bearers. For example, there is significant interest in WiMAX and Wi-Fi as complementary solutions. Can a hybrid approach of public and private networks offer the best of both worlds‾
- Use of commercial networks - these are pushing to offer higher and higher data speeds, while 3G enhancements, such as HSPA+ and LTE, are going head to head with alternative technologies such as WiMAX. When the first round of TETRA networks were being considered the use of commercial networks was ruled out, primarily because of poor resilience and functionality. Are commercial networks mature enough to now be considered as a suitable platform‾
- Complementary Enhancements to TETRA - these include TETRA Enhanced Data Service (TEDS), which has been slow to materialise, and even before it has come to market discussions have started about a broadband successor to TEDS ("˜TEDS2')
- Cognitive radio technology - this an area that is of great interest to regulators because of its potential to make more effective use of spectrum. It seems unlikely that this can be used for mission critical services, but perhaps it could be used to complement new networks.
Spectrum scarcity
While it is too early to predict which solutions will dominate, it is important to remember that whatever the technology, there are long lead time ¬- ten years if the first generation was anything to go by.
Moving towards new networks is not just a matter of choosing the most viable technologies. Public safety organisations may have to fight for spectrum in an increasingly competitive commercial world. So far no additional pan-European spectrum for new services, such as high-speed data public safety use, has been secured, and there will be fierce competition for the prime UHF spectrum released by the switch-off of analogue television signals in Europe.
Lobbying initiatives by bodies, such as the TETRA Association and Public Safety Communications Europe Forum, to secure spectrum for Public Protection and Disaster Relief (PPDR) is ongoing but it will be a tough fight.
Users and operators must act now to ensure that future networks are capable of providing the critical services on which public safety users rely.