Microwave Journal

What is Packet Microwave?

July 15, 2010

Next Generation Microwave Radio Features

So-called Next Generation radios are designed—not surprisingly—to support Next Generation broadband networks and have evolved a set of features that take advantage of the packetized nature of Ethernet/IP traffic to make maximum use of the available licensed spectrum.

Next Generation microwave features generally include all or a combination of the following:
• Software scalable high capacity, with throughputs of 1 Gbit/s or more in a single radio channel
• Native IP transport with built-in Layer 2 Ethernet switching
• Intelligent use of spectrum using Adaptive Coding and/or Modulation, combined with co-channel operation with XPIC
• Legacy TDM traffic supported natively (hybrid) and/or using emulation technologies such as Pseudowire (PWE)
• Packet synchronization support (e.g., IEEE 1588v2, Synchronous Ethernet)
• Advanced OAM (Operations, Administration, and Management) to ITU-T Y.1731, IEEE 802.1ag and IEEE 802.1ah
• Support for one or more architecture choices, including all-indoor, split-mount and all-outdoor

Defining Packet Microwave

There is no industry standard definition of what constitutes a Packet Microwave radio, which has led to a variety of claims from various vendors. To provide an answer, it is helpful to examine what is not a Packet Microwave radio. To support the emerging need to transport Ethernet/IP, traditional microwave of the type found on the market before 2003, typically relied upon external adapters that encapsulated Ethernet packets within TDM frames, whether that was E1/DS1 or virtual containers in the case of SDH/SONET. This service adaptation was inefficient, involving additional overhead that wasted RF bandwidth and introduced latency. Despite what some vendors claim, not a single vendor on the market still offers this type of solution for Ethernet transport.

In contrast, Packet Microwave has been on the market in one form or another for some time. Beginning around 2003, microwave products became available with integrated Ethernet interfaces (i.e., 10/100/1000BaseT), which enabled Ethernet packets to be mapped directly onto the radio airframe, without any encapsulation, which is the fundamental definition of a Packet Microwave radio.