Ultra Low Energy (ULE) Digital Enhanced Cordless Telecommunications (DECT) is a modern communication standard that was adopted by many communication vendors. A DECT ULE base station may communicate with other DECT ULE devices and may control the communication between itself and the other DECT ULE devices.
A communication channel between a DECT ULE base station and DECT ULE devices is used for conveying data packets (such as events (e.g. alarm), measurement (e.g. temperature, AC power consumption, etc.)) and additional information such as configuration and control of devices.
The DECT ULE standard reuses a structure of a 160 ms superframe defined in the original DECT standard. Each superframe includes sixteen 10 ms frames, and each frame includes twenty four timeslots (slots). As there are ten different frequency carriers there are 240 slot/carrier pairs.
A DECT ULE frame is nominally split into two equal halves—slots 0-11 are allocated for down-link transmission (base station to device) and slots 12-23 are allocated for up-link transmission (devices to base station).
A DECT ULE frame can also be used as a bearer. A bearer is a periodic transmission on a particular slot/carrier pair. A bearer can be a traffic bearer or a dummy bearer (also known as beacon).
DECT ULE reuses the Dummy Bearer/Beacon of DECT and adds new fields to it, to address the needs of DECT ULE devices. The dummy bearer usage in DECT ULE has the following challenges:                a. Support of a big number of DECT ULE devices. Unlike the original DECT which supports up to 12 handsets concurrently, DECT ULE must support hundreds of devices        b. Variable latency for different types of devices. For example, devices that are responsible for switching of light should have very short latency (up to ˜40 msec), while other devices (e.g. metering devices) can tolerate many tenths of seconds latency. Thus, the latency of the DECT ULE paging channel needs to be flexible and configurable.        c. Flexibility—the beacon is a scarce resource in terms of bits and bandwidth available . . . . Thus, it is important to reuse the same fields for different purposes (e.g. paging/broadcast), as well as keep possibility to still extend the same fields for future use (e.g. Information Elements, similar to 802.11 beacons) by reuse/overload.        