Point-to-point NDL solves linking problem in the Middle East

MiMOMax solved Baud Telecom Company’s (BTC) problem of linking remote P25 digital radio infrastructure by providing its point-to-point network digital link to one of the company’s public safety users.

BTC is a telecommunications systems integrator based in Jeddah, Kingdom of Saudi Arabia. Established in 1975, it has provided numerous solutions, including wireless, telephony, data network, back-up power and audio and video conferencing, primarily to the Middle East.

The company was faced with the challenge of finding the best solution to link very remote P25 digital radio infrastructure for one of its public safety users in the Middle East.

A wireless linking solution needed to be chosen that provided very high reliability linking over long distances (up to 115 km) with numerous environmental constraints.

These constraints included: low latency suitable for mission-critical voice applications; very high atmospheric temperatures; sites up to 2134 m high; multipath-induced fading issues common in the area; high availability expectations for critical voice streaming where the links had to remain up and running 99.9% of the time; specific narrowband frequencies of 350-380 MHz and 430-460 MHz were also required.

The company chose the spectrally efficient, low-latency, long-range, point-to-point network digital link (NDL) from MiMOMax.

The point-to-point linking solutions provide up to 10 x P25 trunked channels in QAM256 and low latency, typ 8 ms in a 25 kHz channel. The NDL supports all open network standards including MPT 1327, P25, DMR, TETRA and QS Simulcast in trunked and conventional configurations, while supporting seamless analog to digital transition using G711.

Based on the ‘work-with model’, MiMOMax engineers remotely dialled into the user’s MiMOMax NDL system from its head office in Christchurch, New Zealand, and provided timely recommendations that assisted the end user to tune the system to achieve its goals. This level of support was available with the help of advanced remote over-the-air configuration and diagnostic capability built into all MiMOMax radios.

The IP radios can store up to 48 hours of system performance further supported by event-driven captures, thereby enabling fast remote diagnosis and remedial action to take place, often without costly site visits.

MiMOMax also designed a special high-gain antenna to address the challenge of keeping the link available 24/7 without failure, over very long paths. The standard lightweight loop Yagi antenna provides typical gains of up to 12 dBi. However, this customised antenna consisting of four loop Yagi antennas, mounted as two-by-two array on a common frame, was constructed as a quad array.

Implemented at both ends of the link, the quad-array loop Yagi resulted in total improvement of 12 dB path gain.

The smooth rollout of the NDL system was said to be the result of the quality working relationship between BTC, MiMOMax and BTC’s public safety end user.

The radios have provided up to 10 trunked channels in QAM256 and still have 116 Kbps residual ethernet bandwidth available to manage the P25 radios. The MiMO links ensured reliable low error communications even in fading environments, all of which have resulted in improved network efficiency. More data throughput in less RF bandwidth also meant substantial spectrum and cost savings.

The radios deployed were equipped with remote configuration, control and monitoring software (CCMS) that allows system operators to access their network ‘over-the-air’ (web-based) without having to visit the site physically. This real-time access resulted in reduced travel time and lower associated support costs. Furthermore, the radios have the capability of integrating seamlessly with other on-site IP-based equipment, for example, Cisco routers. This flexibility meant ease of implementation and reduction in the system cost of ownership.

By customising the loop Yagi antennas for increased path gain, the end user now has high network availability over long paths in remote areas where most technologies fail to perform at their optimum level. The consistent link availability means high network reliability.

Post-sales support service was also provided including on-site and off-site ‘hands-on’ training sessions with BTC and its end users. This level of user support means that BTC’s end user can rely on support when faced with technical challenges, thereby improving its own user service.