Spectrum is essentially what makes it possible for the consumer to tune in to a radio station, be able to watch television or make a phone call. This is a very important resource. Its misuse or misapplication could mean that the consumer is unable to make phone calls, use data or watch TV and listen to the radio, etc. Spectrum also makes it possible for aircraft to be communicated to before take-off and landing. All of these activities happen because of the availability of the spectrum. Spectrum Management is simply the process of regulating the use of radio frequencies to promote efficient use and gain a net social benefit. It ensures interference-free access to the radio frequency spectrum for as many users and as many uses as is possible. Spectrum as a finite resource has to be managed judiciously so that the state and businesses gain the most from its usage.
Mandate of the NCA on Spectrum Management
As the Communications Regulator, Sections 2 and 58 of the Electronic Communications Act, 775 (2008) mandate the National Communications Authority (NCA) to regulate the radio frequency spectrum for broadcasting and telecommunication in accordance with the applicable standards and requirements of the International Telecommunication Union and its Radio Regulations, as agreed to or adopted by the Republic. In carrying out this function, Section 67 (2) of Act 775 enjoins the Authority to identify, adopt or establish preferred technical standards in Regulations or where necessary, require conformity to a stated standard. These standards form a part of the conditions of all frequency authorisations and the Authority is mandated by Section 62 of Act 775 to establish frequency monitoring stations to monitor compliance with standards.
Previous Approach to Spectrum Management – Spectrum Monitoring System (SMS)
In 2009, the NCA acquired the Spectrum Monitoring System (SMS) to among others;
• Monitor Authorisation and Licence conditions of Operators
• Conduct Radio Frequency Interference investigation
The Authority currently has five (5) mobile Spectrum Monitoring stations and four (4) fixed stations in Accra, Kumasi, Takoradi, and Tamale. The Authority also has Portable Spectrum analysers to complement the work of the monitoring stations
Gaps Which Required the Authority’s Action:
The SMS provided effective spectrum monitoring but did not provide a mechanism for service-specific signal analysis, especially for broadcasting services. Following the country’s decision to migrate from analogue to digital, there was a need for a detailed analysis of Digital Terrestrial Television (DTT) services to support this transition. For example, although the SMS can measure the signal strength of a DTT signal, it could not provide the modulation characteristics, bit rate and Service Information (SI), and Programme Specific Information (PSI), among others. It was also imperative to conduct continuous monitoring of FM radio broadcasting services and Radio Data Services (RDS) with the use of adjacent frequency channels in the same location. However, the SMS was unable to provide a continuous unattended measurement of broadcasting services and did not have a mechanism to record broadcast transport streams for evidence during enforcement.
Background (Broadcast Monitoring)
To bridge the gaps identified on the SMS, the Authority has since 2018 acquired the Broadcasting Monitoring System (BMS) to facilitate the comprehensive monitoring of broadcasting services. The BMS has been set up to serve as a complementing tool to the SMS by monitoring the technical requirements of FM and TV Authorisation holders and SMS.
The system comprises:
• Monitoring Work Station
• Receiving system: 4 DVB-T2/S2 and 10 FM Tuners
• Broadcast server and storage (96TB)
For TV Broadcasting, the system can monitor EPG information, Logical Channel Numbering, Encryption, Signal Strength, Signal Quality and Error Loggings (Frozen screen, Black screen, Silent audio), Sound/Video format, Loudness, and other Technical parameters such as SI/PSI table information (EIT, NIT, PID, Transmission data rates, etc.). Key monitoring parameters for FM Broadcasting entails MPX Deviation (bandwidth use), Signal strength, RDS information, and Audio levels. This newly acquired tool enables the NCA to see first-hand the technical operations of Broadcast Authorisation holders and to respond promptly to infractions. It also enables the Authority to obtain real-time measurements of FM Radio and television signal and service quality.
The main objectives of the BMS are:
• To monitor the quality of service of FM Radio and Television broadcasting stations.
• To determine the technical parameters of FM Radio and Television broadcasting stations.
• To provide recording and/or logging of both broadcast content and technical metrics.
Installations in Ghana
Currently, the NCA has deployed fixed stations in Accra, Kumasi, and Tamale and mobile systems in Koforidua, Bolgatanga, Sunyani, and the Head Office (Accra). The fixed stations will be expanded to cover Takoradi, Koforidua, and Ho by the end of November 2019.
While the BMS installed at the Head Office facilitates the comprehensive monitoring of broadcasting services in and around Accra, the installations in the other regions provide in-depth off-air digital terrestrial television (DTT) and FM Radio monitoring in other parts of the country.
This decentralisation is significant since the National DTT network is designed to transmit on two multiplexes – a national multiplex on the same frequency with the same content throughout the country and Regional multiplexes with some channels specific to particular regions.
Benefits to Industry and Consumers
As a Regulator, the BMS has been of immense benefit to the NCA’s Regulatory work.
Some of the benefits are:
1. The NCA can meet ITU-R requirements for the measurement of FM and TV transmission parametres. For example, the 15-minute observation time required by ITU-R for FM deviation can always be met.
2. The Authority can show proof of deviations for enforcement in this era of Tribunal & Court suits from sanctioned stations.
3. Ability to provide DTT quality analysis for the National Network on a real-time basis. This will also provide technical information to support consumer education during the transition.
4. Ensuring better broadcast service quality for consumers
5. Detection of unauthorised broadcast