Point-to-Multipoint Networks
Long Distance Communications for Fixed and Mobile Assets
Point-to-Multipoint mode (PtMP) is one of two operating modes
supported by IEEE 802.16t. This mode supports communication from
remote radios (installed in fixed locations or mobile vehicles) to the
office and from the office to the remote radios through the base
station to which the remote radios are connected.
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Communication between base stations and remotes is performed
over an IEEE 802.16t subchannel group which consists of multiple
adjacent or non-adjacent subchannels. IEEE 802.16t PtMP employs
Time Division framing to separate in time the transmission from the
base stations to the remotes (this is referred to as Downlink) and the
transmission from the remotes to the base stations (this is referred to
as Uplink). The transmission in the downlink and in the uplink direction can be done in the same frequency (this is referred to as Time Division Duplex or TDD) or in distinct frequencies (this is referred to as Half Duplex Frequency Division Duplex or HD-FDD).​
Scheduling Modes Used in PtMP
IEEE 802.16t PtMP is a scheduled air interface protocol. Any communication between the base station to its connected remotes in both directions is scheduled by the base station scheduler. The base station scheduler supports the following scheduling modes:
Standalone Scheduling
In this mode, base stations operate independently without a Base Station Controller (BSC). Each base station has a fixed configuration of resources—such as specific frequency bands—and allocates these resources for communication with connected remote radios. This mode is ideal for simpler setups where the base station manages its own resources without external control.
Secondary Scheduling
When a Base Station Controller (BSC) is in place, secondary scheduling allows for dynamic resource allocation. The BSC assigns specific Air Interface Resources (AIRs) to each base station under its control. These base stations then use the assigned AIRs to communicate with their remote radios. This approach allows for more efficient management of resources, especially in large or complex network setups, where the allocation of bandwidth and time slots needs to be adjusted based on real-time traffic demands.
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Learn more about the BSC here.
Ondas Networks FullMAX™ Radios
Scalable and Secure Wireless Networks for Connected Wayside Applications
Mercury
Mercury is an ultra- compact, low-cost, endpoint radio for mission-critical data applications at wayside locations. Mercury's small form factor and ruggedized enclosure make it an ideal solution for networking locations such as railroad crossings and defect detectors. Mercury radios operate over a single subchannel with dynamically adjusted modulation coding schemes.
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Neptune
The high-power Neptune radio can operate as a long range endpoint radio or as a base station providing coverage with other Neptune, Venus, and Mercury endpoint radios in an 802.16t network. Operating over a single or multiple subchannels, Neptune offers the highest data throughput across contiguous and non-contiguous channels in any frequency band at distances over 30 miles.
Venus
The versatile Venus radio can operate as an endpoint radio or as a base station providing coverage with other Venus and Mercury endpoint radios. Venus radios can operate over a single or multiple subchannels, offering higher data throughput across contiguous and non-contiguous channels in any frequency band. With a 4W output, Venus is designed to support longer range communications
Mars
The high-performance Mars is an IEEE 802.16t radio utilized to provide coverage to hundreds of 802.16t remote radios. Typically serving as a high-power base station in a Point-to-Multipoint network, Mars connects to Ondas Venus and Mercury endpoint radios in order to provide speed IP communications over very long distances using narrowband channels.
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Why Choose a Point-to-Multipoint Architecture?
802.16t Standards Built for Railroads and IoT
Flexible Deployment Options
Connect remote radios in both fixed locations and mobile vehicles through a centralized base station, ensuring seamless communication in various environments.
Advanced Scheduling for Reliable Communication
Scheduling within PtMP networks allocates time slots for each radio, preventing congestion and ensuring consistent, smooth data transmission.
Maximized Spectrum Efficiency
Time Division framing separates uplink and downlink traffic, optimizing bandwidth use and ensuring reliable communication during high-demand periods.
Adaptable Frequency Management
Choose between TDD or HD-FDD modes for optimized frequency management, tailored to your specific operational requirements.
Dynamic Resource Allocation
Base stations and Base Station Controllers dynamically manage resources to maintain efficient communication, even in high-traffic conditions.
Scalable for Diverse
Use Cases
PtMP networks support a range of applications, from rail operations to smart grid connectivity and field team communications, offering a robust solution for mission-critical needs.
Point-to-Multipoint (PtMP) Compared to Direct Peer-to-Peer (DPP) Networks
While IEEE 802.16t Point-to-MultiPoint (PtMP) utilizes base stations to provide long range communications for various fixed and mobile assets, DPP allows direct, peer-to-peer communication without an intermediary base station. This makes DPP a more flexible option in certain use cases.
PtMP
Best for wide-area, fixed infrastructure like smart grids and rail operations.
DPP
Ideal for smaller-scale, mobile networks like field teams or temporary installations.
Common Applications
Rail Operations
Enhance wide-area rail connectivity for operational safety and efficiency.
Smart Grid Extensions
Connect remote substations to central systems for better network management.
Field Team Coordination
Link mobile teams with headquarters for real-time updates and decision-making.