Method, base station, and user equipment for accessing physical random access channel

A method for accessing a physical random access channel (PRACH), the method comprising:

• receiving an indication parameter of a PRACH sequence group used by multiple base stations, wherein the multiple base stations use a same cell identity and comprise a macro base station and at least one pico base station, the PRACH sequence group based on two root sequences, a first root sequence associated with the macro base station and a second root sequence associated with the pico base station, and the indication parameter is used for indicating first PRACH sequences to sixth PRACH sequences, wherein the first PRACH sequences to the sixth PRACH sequences are comprised in the PRACH sequence group;
• determining, according to the indication parameter, that the PRACH sequence group comprises k1 first PRACH sequences, k2 second PRACH sequences, k3 third PRACH sequences, k4 fourth PRACH sequences, k5 fifth PRACH sequences, and k6 sixth PRACH sequences, wherein k1 and k4 are positive integers, and k2, k3 , k5, and k6 are nonnegative integers, wherein the first PRACH sequences to the third PRACH sequences are based on the first root sequence and the fourth PRACH sequences to the sixth PRACH sequences are based on the second root sequence;
• and
• selecting a PRACH sequence from the PRACH sequence group to randomly access a network.

A method for accessing a physical random access channel PRACH, the method comprising:

• determining M PRACH sequence groups used by L groups of base stations, wherein the L groups of base stations use a same cell identity, each PRACH sequence group of the M PRACH sequence groups comprises m1 first PRACH sequences, m2 second PRACH sequences, and m3 third PRACH sequences, M and L are positive integers and 1<M≦L, m1 is a positive integer, and m2 and m3 are nonnegative integers;
• and
• multiplexing the M PRACH sequence groups in the L groups of base stations according to geographic locations of the L groups of base stations;
• sending an indication parameter of the PRACH sequence group to a user equipment UE for the UE to randomly access a network, wherein the indication parameter is used for indicating the first PRACH sequences to the third PRACH sequences, wherein the first PRACH sequences to the third PRACH sequences are comprised in each PRACH sequence group of the M PRACH sequence groups.

A method for accessing a physical random access channel PRACH, the method comprising:

• receiving an indication parameter of M PRACH sequence groups used by L groups of base stations, wherein the L groups of base stations use a same cell identity, and the indication parameter is used for indicating first PRACH sequences to third PRACH sequences, wherein the first PRACH sequences to the third PRACH sequences are comprised in each PRACH sequence group of the M PRACH sequence groups;
• multiplexing the M PRACH sequence groups in the L groups of base stations according to geographic locations of the L groups of base stations;
• determining, according to the indication parameter, that each PRACH sequence group comprises m1 first PRACH sequences, m2 second PRACH sequences, and m3 third PRACH sequences, wherein M and L are positive integers and 1 <M<L, m1 is a positive integer, and m2 and m3 are nonnegative integers;
• and
• selecting a PRACH sequence from the PRACH sequence group to randomly access a network.

A base station, comprising:

• a determining unit, configured to determine a physical random access channel PRACH sequence group used by multiple base stations, wherein the multiple base stations use a same cell identity and comprise a macro base station and at least one pico base station, the PRACH sequence group comprises k1 first PRACH sequences, k2 second PRACH sequences, k3 third PRACH sequences, k4 fourth PRACH sequences, k5 fifth PRACH sequences, and k6 sixth PRACH sequences, wherein k1 and k4 are positive integers, and k2, k3 , k5, and k6 are nonnegative integers;
• and
• a sending unit, configured to send an indication parameter of the PRACH sequence group determined by the determining unit, to a user equipment UE for the UE to randomly access a network, wherein the indication parameter is used for indicating the first PRACH sequences to the sixth PRACH sequences;
• wherein the first PRACH sequences and the fourth PRACH sequences, determined by the determining unit, are PRACH sequences of contention-based Group A, the second PRACH sequences and the fifth PRACH sequences are PRACH sequences of contention-based Group B, and the third PRACH sequences and the sixth PRACH sequences are non-contention based PRACH sequences.

A user equipment, comprising:

• a receiving unit, configured to receive an indication parameter of a physical random access channel PRACH sequence group used by multiple base stations, wherein the multiple base stations use a same cell identity and comprise a macro base station and at least one pico base station, the PRACH sequence group based on two root sequences, a first root sequence associated with the macro base station and a second root sequence associated with the pico base station, and the indication parameter is used for indicating first PRACH sequences to sixth PRACH sequences, wherein the first PRACH sequences to the sixth PRACH sequences are comprised in the PRACH sequence group;
• a determining unit, configured to determine, according to the indication parameter received by the receiving unit, that the PRACH sequence group comprises k1 first PRACH sequences, k2 second PRACH sequences, k3 third PRACH sequences, k4 fourth PRACH sequences, k5 fifth PRACH sequences, and k6 sixth PRACH sequences, wherein k1 and k4 are positive integers, and k2, k3, k5, and k6 are nonnegative integers, wherein the first PRACH sequences to the third PRACH sequences are based on the first root sequence and the fourth PRACH sequences to the sixth PRACH sequences are based on the second root sequence;
• and
• a selecting unit, configured to select a PRACH sequence from the PRACH sequence group determined by the determining unit to randomly access a network.

A user equipment, comprising:

• a receiving unit, configured to receive an indication parameter of M physical random access channel PRACH sequence groups used by L groups of base stations, wherein the L groups of base stations use a same cell identity, and the indication parameter is used for indicating first PRACH sequences to third PRACH sequences, wherein the first PRACH sequences to the third PRACH sequences are comprised in each PRACH sequence group of the M PRACH sequence groups, the M PRACH sequence groups multiplexed in the L groups of base stations according to geographic locations of the L groups of base stations;
• a determining unit, configured to determine, according to the indication parameter, that each PRACH sequence group comprises m1 first PRACH sequences, m2 second PRACH sequences, and m3 third PRACH sequences, wherein M and L are positive integers and 1<M<L, m1 is a positive integer, and m2 and m3 are nonnegative integers;
• and
• a selecting unit, configured to select a PRACH sequence from the PRACH sequence group to randomly access a network.