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Table 2 Notation Summary

From: Utility-based efficient dynamic distributed resource allocation in buffer-aided relay-assisted OFDMA networks

Notation

Description

\(\mathcal {N}, N\)

Set and total number of subchannels, respectively

\(\mathcal {M}, M\)

Set and total number of relays, respectively

\(\mathcal {K}, K\)

Set and total number of users, respectively

\(\mathcal {B}\)

Set of all the serving nodes, including the BS and relays

\(\mathcal {K}_{m}\)

Set of users connected to node m

\(\mathcal {Q}_{m}\)

Set of users that have a buffer in node m

m(k)

Serving node of user k

T

Duration of a time slot

B

Bandwidth of a subchannel

Γ k

SNR gap for user k

\(e^{m}_{\textit {kn}}(t), x^{m}_{\textit {kn}}(t)\)

Channel gain-to-noise ratio and subchannel allocation indicator of subchannel n in time slot t, respectively, for the link of user k from node m

\(r^{m}_{\textit {kn}}(t), \tilde {r}^{m}_{\textit {kn}}(t)\)

Achievable transmission rate and estimated achievable transmission rate on subchannel n in time slot t, respectively, for the link of user k from node m

\({r^{m}_{k}}(t)\)

Total transmission rate on the link of user k from node m in time slot t

\({p^{m}_{n}}(t)\)

Power used by node m on subchannel n in time slot t

\(P_{m}(t), \hat {P}_{m}, P^{av}_{m}\)

Total power to be used in time slot t, peak power constraint and average power constraint, respectively, for node m

\({L^{m}_{k}}, {Q^{m}_{k}}(t)\)

Capacity of MAC layer buffer of user k in node m and the queue size in it in time slot t, respectively

\({a^{m}_{k}}(t)\)

Size of data arrived at the MAC layer buffer of user k in node m in time slot t

\(\hat {a}\)

Upper bound of data admission into a buffer in the MAC layer of the BS

J k ,Y k (t),A k (t)

Capacity, queue size and the arrived data size in time slot t, respectively, in the top layer buffer of user k in the BS

\(\mathcal {U}(.), V\)

Utility function and the value coefficient for it, respectively

γ k (t),G k (t)

Auxiliary variable corresponding to data admission of user k and its corresponding virtual queue size, respectively, in time slot t

Z m (t),I

Virtual power queue size of node m in time slot t and the importance factor, respectively, corresponding to average power constraints

\({\rho ^{m}_{k}},W_{e}\)

Indicator variable for the link of user k from node m and the extra weight, respectively, for providing fair data admission

\(\tilde {N}_{m}, \hat {N}_{m}\)

Estimation of node m for its number of subchannels and the upper bound considered by the BS on the number of subchannels for node m, respectively

\({D^{m}_{n}}, D^{m}\)

Average demand of relay m on subchannel n and average total demand of node m, respectively

\(D^{0a}_{n}, D^{0a}\)

Average demand of the BS on subchannel n and average total demand of the BS, respectively, for type A time slot

\(D^{0b}_{n}, D^{0b}\)

Average demand of the BS on subchannel n and average total demand of the BS, respectively, for type B time slot

D A,D B

Total demand for type A and type B time slots, respectively