Alcatel-Lucent MDR-8000 MDR-8706-8 Microwave Digital Radio System – Detailed Review

The Alcatel-Lucent MDR-8000 series, specifically the MDR-8706-8 configuration, is a high-capacity microwave digital radio system designed for point-to-point telecommunications trunking. This rack-mountable unit features a modular bay capable of housing up to eight (8) individual radio or interface modules, providing unprecedented flexibility for network operators to tailor capacity, redundancy, and frequency band usage according to specific link requirements. The MDR-8000 series is renowned for its rugged construction, outstanding thermal stability, and exceptional spectral efficiency.

The MDR-8706-8 chassis is a 5U high, 19-inch rack unit with a backplane that supports hot-swappable plug-in modules. The system can be populated with a mix of RF transceivers covering frequency bands from 6 GHz to 38 GHz, along with modem cards, protection switching units, and multiplexer modules. This modular approach allows operators to start with a minimal configuration and scale up capacity by adding modules over time, protecting initial investment while enabling gradual network growth.

Each radio module within the MDR-8706-8 supports high-level modulation schemes up to 2048 QAM in some variants, delivering aggregate capacities of up to several hundred megabits per second per carrier. The system is fully compliant with both PDH (Plesiochronous Digital Hierarchy) and SDH (Synchronous Digital Hierarchy) standards, supporting E1/T1, E3/T3, and STM-1/OC-3 interfaces through interchangeable tributary cards. This dual compliance makes the MDR-8000 equally suitable for legacy TDM networks and modern packet-based backhaul infrastructures.

One of the standout features of the MDR-8706-8 is its robust protection switching capability. The system supports 1+1 and N+1 hot-standby configurations with automatic switchover in less than 50 milliseconds, ensuring carrier-grade availability of 99.999%. The protection switching is driven by real-time error monitoring (BER, RSL, and synchronization status), with user-configurable thresholds and revertive or non-revertive modes. The diversity combiner option allows for frequency or space diversity configurations to combat multipath fading.

Network management is handled via the embedded MDR-8000 Element Manager or through third-party SNMP platforms using standard MIBs. The system provides comprehensive performance monitoring for each module, including transmitter power, frequency offset, modulation error, and antenna voltage standing wave ratio (VSWR). Historical performance data is retained for up to 30 days, facilitating trend analysis and predictive maintenance. The management interface also supports remote software upgrades and configuration file backup/restore.

Mechanically, the MDR-8706-8 chassis is built from heavy-gauge steel with a corrosion-resistant powder coat finish. Cooling is provided by redundant, field-replaceable fan trays that draw air from front to back, ensuring consistent temperatures across all modules. The fan speed is thermally controlled to minimize noise while maintaining adequate airflow under high ambient temperatures. The unit operates in environments ranging from -5°C to +50°C and up to 95% relative humidity.

Power input is dual-redundant, with two -48 VDC terminal blocks supporting load-sharing and automatic failover. The system can also be equipped with optional AC power supplies for office environments. The backplane includes dedicated power rails with circuit protection for each slot, ensuring that a faulty module does not affect the entire system. Typical power consumption for a fully populated system is under 300 W, depending on the specific module mix.

Interface connectivity includes front-panel access for all tributary and management ports. The system provides multiple BNC, RJ-45, and fiber-optic (SFP) connections for user traffic, along with a dedicated RS-232 craft port for local terminal access. LED indicators on each module and the front panel provide at-a-glance status for power, link, alarm, and traffic activity. A comprehensive alarm system includes visual, audible, and dry-contact relay outputs for integration into central office monitoring systems.

Regulatory compliance for the MDR-8706-8 includes ETSI EN 302 217, FCC Part 101, and IC RSS-210 for radio performance. The system also meets NEBS Level 3 (GR-63-CORE and GR-1089-CORE) requirements for shock, vibration, fire resistance, and electromagnetic compatibility, making it suitable for deployment in regional telecom central offices and carrier hotel facilities.

Installation and commissioning are streamlined through an intuitive, menu-driven local interface that guides technicians through frequency setting, power adjustment, and alignment procedures. The system includes an integrated RSL measurement tool that provides both numeric readouts and audible tones for antenna alignment without requiring external test equipment. The MDR-8000 also supports an automatic frequency scanning feature to assist in site survey and interference identification.

In summary, the Alcatel-Lucent MDR-8000 MDR-8706-8 is a versatile, high-capacity microwave radio system that excels in demanding trunking applications. Its eight-module bay, combined with advanced protection schemes, comprehensive management, and modular scalability, provides a future-proof solution for mobile backhaul and private network operators. The MDR-8706-8 upholds Alcatel-Lucent’s tradition of engineering excellence, delivering the performance and reliability required for critical communications infrastructure.