TDMA communication device and method to select a transmission slot with reduced risk of collision

1. A TDMA communication device within an own station, comprising:

a receiver configured to receive communication data from another station through any of a plurality of reception slots within a selection interval set based on a given nominal increment; and

processing circuitry configured to:

detect a first reception slot position and a second reception slot position,

acquire the given nominal increment and time length of the selection interval-based on the communication data received from another station,

estimate an estimated maximum selection interval based on the time length of the selection interval and the first reception slot position,

estimate a first temporary estimation selection interval based on the first reception slot position, the given nominal increment, and the estimated maximum selection interval,

estimate a second temporary estimation selection interval based on the time length of a selection interval and the second reception slot position,

estimate an estimated selection interval based on the first temporary estimation election interval and the second temporary estimation selection interval,

set a transmission slot for the own station based on the estimated selection interval, and

transmit data from the own station using the set transmission slot.

2. The TDMA communication device of claim 1 , wherein the processing circuitry is further configured to:

estimate an overlapped section of the first temporary estimation selection interval and the second temporary estimation selection interval as the estimated selection interval of another station.

3. The TDMA communication device of claim 2 , wherein

the processing circuitry is further configured to:

estimate a first temporary slot selection interval assuming the position of the first slot is a first slot of the selection interval,

estimate a second temporary slot selection interval assuming the position of the first slot is a last slot of the selection interval,

estimate a section included in any of the first temporary slot selection interval and the second temporary slot selection interval as an estimated maximum selection interval for the first slot, and

estimate the first temporary estimation selection interval by delaying the estimated maximum selection interval for the given nominal increment.

4. The TDMA communication device of claim 2 , wherein

the processing circuitry is further configured to:

estimate a third temporary slot selection interval assuming the position of the second slot is a first slot of the selection interval,

estimate a fourth temporary slot selection interval assuming the position of the second slot is a last slot of the selection interval, and

estimate a section included in any of the third temporary slot selection interval and the fourth temporary slot selection intervals as the second temporary estimation selection interval.

5. The TDMA communication device of claim 2 , wherein

the processing circuitry is further configured to:

use a position of a third slot different from the first slot and the second slot,

update the overlapped section by using the second temporary estimation selection interval calculated based on at least one of previous time estimated selection intervals of another station, and the position of the third slot, and

estimate the estimated selection interval of another station based on the updated overlapped section.

6. The TDMA communication device of claim 1 , wherein

the processing circuitry is further configured to:

set a transmission slot of the own station based on the estimated selection interval of another station, and a selection interval of the own station.

7. The TDMA communication device of claim 6 , wherein

the processing circuitry is further configured to:

detect an existence of an overlap of the estimated selection interval of another station and the selection interval of the own station, and

set non-overlapping slots as the transmission slot of the own station.

8. The TDMA communication device of claim 6 , wherein

the processing circuitry is further configured to:

calculate a collision probability that is a probability that each slot in the selection interval of the own station collides with a transmission slot of another station based on the estimated selection interval of another station and the selection interval of the own station, and

set the slot with a low collision probability as the transmission slot of the own station.

9. The TDMA communication device of claim 8 , wherein

the collision probability is a logarithm.

10. A TDMA communication method, comprising:

receiving communication data from another station through any of a plurality of reception slots within a selection interval set based on a given nominal increment;

acquiring the given nominal increment and time length of the selection interval based on the communication data received from another station;

estimating an estimated maximum selection interval based on the time length of the selection interval and the first reception slot position,

estimating a first temporary estimation selection interval based on the first reception slot position, the given nominal increment, and the estimated maximum selection interval,

estimating a second temporary estimation selection interval based on the time length of a selection interval and the second reception slot position,

estimating an estimated selection interval based on the first temporary estimation election interval and the second temporary estimation selection interval,

set a transmission slot for the own station based on the estimated selection interval, and

transmit data from the own station using the set transmission slot.