System and method for improving network access in machine to machine communication
View Patent ↗An apparatus may include a processor circuit and an adaptive access module operable on the processor circuit to schedule broadcast of random access resources to access a radio network and to adaptively adjust an initial backoff window size for access signaling to the radio network during an access period. Other embodiments are disclosed and claimed.
1. An apparatus, comprising:
a processor circuit; and
an adaptive access module operable on the processor circuit to adaptively adjust a backoff window size used for access signaling to a radio network during an access period based on access loading estimates of a random access load from multiple machine to machine (M2M) devices in communication with the radio network, the backoff window size comprising a wait time for retry of transmission by two or more M2M devices when a collision occurs between communications from the two or more M2M devices, the adaptive access module operable on the processor circuit to schedule a broadcast of one or more messages to a group of M2M devices for use in accessing the radio network, the one or more messages to include an initial ranging backoff start field with an initial backoff window size value.
2. The apparatus of claim 1 , the one or more messages to comprise paging advertisement messages.
3. The apparatus of claim 1 , the adaptive access module operable to increase the backoff window size when access loading estimates increase, and decrease the backoff window size when access loading estimates decrease.
4. The apparatus of claim 1 , the adaptive access module operable on the processor circuit to determine access loading λ(t) according to:
λ
(
t
)
=
α
*
M
(
t
)
N
(
t
)
where M(t) is the total number of ranging channels being used in an access window t,
where N(t) is the total number of available ranging channels in an access window t, and
where α is a weight coefficient constant.
5. The apparatus of claim 4 ,
the adaptive access module operable on the processor circuit to measure M(t) based upon random access code received over an air interface during the access window t.
6. The apparatus of claim 4 ,
the adaptive access module operable on the processor circuit to measure N(t) by counting random access resource available in the access window t.
7. The apparatus of claim 4 ,
the adaptive access module operable on the processor circuit to determine an average access loading estimation λ avg according to
λ avg ( T k )=mean(λ( t )), tε[t 0 , . . . ,t 0 +T k ], k= 0,1, . . . .
8. The apparatus of claim 1 , the adaptive access module operable on the processor circuit to adjust an initial backoff window size based upon a target access success ratio r target and an expected access success ratio r as a function of access loading λ(t) for one or more initial backoff window sizes.
9. The apparatus of claim 8 , the adaptive access module operable on the processor circuit to:
determine average access loading λ avg (T−1) in a period T−1;
set r target for a period T;
calculate r as a function of λ(t) for each of multiple values of initial backoff window;
determine a value of r at λ avg (T−1) for one or more values of initial backoff window; and
select an initial backoff window size based upon a comparison of r to r target .
10. The apparatus of claim 1 , comprising a high power antenna to broadcast the initial backoff window size to the radio network.
11. At least one non-transitory computer-readable storage medium comprising a plurality of instructions that, when executed, cause a system to:
adaptively adjust a backoff window size used for access signaling to a radio network during an access period based on access loading estimates of a random access load from multiple machine to machine (M2M) devices in communication with the radio network, the backoff window size comprising a wait time for retry of transmission by two or more M2M devices when a collision occurs between communications from the two or more M2M devices; and
schedule a broadcast of one or more messages to a group of M2M devices for use in accessing the radio network, the one or more messages to include an initial ranging backoff start field with an initial backoff window size value.
12. The at least one non-transitory computer-readable storage medium of claim 11 , the one or more messages to comprise paging advertisement messages.
13. The at least one non-transitory computer-readable storage medium of claim 11 comprising a plurality of instructions that, when executed, cause a system to increase the backoff window size when access loading estimates increase, and decrease the backoff window size when access loading estimates decrease.
14. The at least one non-transitory computer-readable storage medium of claim 11 comprising a plurality of instructions that, when executed, cause a system to determine access loading λ(t) according to:
λ
(
t
)
=
α
*
M
(
t
)
N
(
t
)
where M(t) is the total number of ranging channels being used in an access window t,
where N(t) is the total number of available ranging channels in an access window t, and
where α is a weight coefficient constant.
15. The at least one non-transitory computer-readable storage medium of claim 14 comprising a plurality of instructions that, when executed, cause a system to measure M(t) based upon random access code received over an air interface during the access window t.
16. The at least one non-transitory computer-readable storage medium of claim 14 comprising a plurality of instructions that, when executed, cause a system to measure N(t) by counting random access resource available in the access window t.
17. The at least one non-transitory computer-readable storage medium of claim 14 comprising a plurality of instructions that, when executed, cause a system to determine an average access loading estimation λ avg according to
λ avg ( T k )=mean(λ( t )), tε[t 0 , . . . ,t 0 +T k ], k= 0,1, . . . .
18. The at least one non-transitory computer-readable storage medium of claim 11 comprising a plurality of instructions that, when executed, cause a system to adjust an initial backoff window size based upon a target access success ratio r target and an expected access success ratio r as a function of access loading λ(t) for one or more initial backoff window sizes.
19. The at least one non-transitory computer-readable storage medium of claim 17 comprising a plurality of instructions that, when executed, cause a system to:
determine average access loading λ avg (T−1) in a period T−1;
set r target for a period T;
calculate r as a function of λ(t) for each of multiple values of initial backoff window;
determine a value of r at λ avg (T−1) for one or more values of initial backoff window; and
select an initial backoff window size based upon a comparison of r to r target .