Alcatel Lucent 9500 MPR Microwave Platform Deployment and Troubleshooting

XPIC capacity doubling: In the 6 GHz, 11 GHz, 18 GHz, 23 GHz, and 38 GHz frequency bands, with XPIC enabled, the same channel can simultaneously transmit two horizontally and vertically polarized signals, doubling the capacity. For example, 11 GHz/30 MHz/128 QAM, non XPIC capacity of 162.88 Mb/s, XPIC mode is 162.88 Mb/s × 2 (total 325.76 Mb/s), and the transmission power and threshold remain basically unchanged (see Table 4-6). When deploying the project, it is necessary to ensure that the antenna polarization isolation is ≥ 30 dB, otherwise the XPIC performance will be severely degraded.

Adaptive modulation and lossless switching mechanism

The 9500 MPR supports Hitless Adaptive Modulation, which can automatically adjust the modulation mode (QAM 4/16/32/64/128/256) based on real-time radio conditions such as rain attenuation and multipath fading, and the service is not interrupted (hitless) during the switching process. This is the core function of improving link availability.

Configuration points:

In the management interface of MSS or MPT-HL, set a Modulation Profile for each link, including the allowed highest and lowest modulation levels. For example, it can be configured as "4 QAM ↔  256 QAM "adaptive range.

The system automatically downgrades or upgrades the modulation mode according to a preset switching threshold (triggered by the bit error rate BER) by monitoring the received signal level (RSL) and signal-to-noise ratio (SNR).

When the modulation level decreases, the link capacity automatically decreases, but all high priority services (such as TDM simulation or VoIP) can still obtain priority forwarding through built-in QoS queues, and low priority data services can be flexibly adapted.

Operation and maintenance reminder:

View the current modulation status and switching history: View the radio modulation and adaptive modulation logs through the CLI or Web management interface. If modulation degradation occurs frequently, it indicates that the link margin is insufficient or the antenna alignment is incorrect, and the RF cable, feeder or weather impact needs to be checked.

If a fixed modulation mode (such as a dedicated high-capacity link) is required, the modulation list can be limited to a single mode, but the anti fading ability will be sacrificed.

Synchronization and clock distribution configuration

9500 MPR supports multiple synchronization schemes to meet the strict requirements of frequency and phase synchronization in mobile backhaul:

SyncE (Synchronous Ethernet)+SSM (Synchronous Status Message): Compliant with ITU-T G.8264, it can transmit frequency synchronization signals in a full Ethernet environment without the need for additional clock lines.

IEEE 1588v2 (PTP): Supports precise time synchronization and is suitable for phase synchronization requirements of TD-LTE and 5G base stations (needs to be combined with ODU or MPT-HL versions that support PTP).

External reference clock input/output: Supports 2 MHz, 5 MHz, 10 MHz reference signals, as well as DS1 clock extraction.

Built in Stratum 3 clock: can maintain long-term free oscillation when losing external reference, reducing the risk of chain loss.

Deployment Practice:

In circular or chain microwave networks, it is recommended to use SyncE as the primary synchronization source and configure SSM to achieve automatic clock source selection and switching.

If using 1588v2, it is necessary to ensure that all nodes in the network (including ODU and IDU) support PTP and that the boundary clock (BC) or transparent clock (TC) configuration is correct. The MPT-HL and ODU 300 related models have been labeled as supporting 1588v2, which can be confirmed in the data sheet.

Use the show synchronization command to check the current clock source lock status and SSM quality level.

Business interface and aggregation capability

9500 MPR provides rich user side interfaces (UNI) and network side interfaces (NNI), supporting mixed access of TDM and packet services:

TDM interface: DS1 access card (32 channels of DS1 per card), DS3 access card (2 channels of DS3 per card). Support Circuit Simulation Services (CES) to ensure the timing and latency characteristics of TDM services in packet networks.

Ethernet interface: The control and switching module provides 4 x 10/100/1000BaseT and 2 x SFP (gigabit optical ports); The 8-port Ethernet access card provides 4 x 10/100/1000BaseT+4 x SFP; There are also 2 x DS1 SFPs used for hybrid interfaces.

Link Aggregation (LAG): Supports IEEE 802.1ad link aggregation, which can bundle multiple Ethernet interfaces into logical links to improve bandwidth and redundancy.

Aggregation capability: MSS-8, when combined with EAS (Enhanced Aggregation Service) cards, can achieve a switching capacity of 48 Gb/s, supporting local switching and routing of up to 192 DS1 or large amounts of FE/GE traffic, reducing the occupation of upstream router ports.

Redundancy and high availability design

The 9500 MPR eliminates single point of failure in its design, with key redundancy mechanisms including:

RF channel redundancy: supports 1+1 HSB (hot backup) and 2+0 (dual transmitter and dual receiver) configurations. In HSB mode, when the primary RF channel fails, the backup channel takes over within milliseconds without loss of service. MPT-HL and MSS both support up to 6 pairs of HSB RF (i.e. 6 out of 12 ODUs as backups).