Methods and devices for communicating on a radio channel based on jointly encoding a preamble format with random access configuration

A base station of an evolved UMTS Terrestrial Radio Access Network, EUTRAN, configured to operate in time divisional duplex, TDD, mode, the base station comprising:

• control circuit configured to jointly encode a preamble format with a first random access configuration, thereby forming an extended random access configuration represented by a set of bits, wherein said joint encoding comprises setting a value of each individual bit in the set based on both the preamble format and the first random access configuration, wherein the first random access configuration comprises a combination of:
• a density value defining a density of random access opportunities on a Physical Random Access Channel, PRACH;
• and
• a version index defining one of several possible patterns of opportunities on the PRACH for that density, each pattern allocating opportunities to different sub-frames of the PRACH;
• and
• a transmitting circuit configured to transmit the extended random access configuration on a radio channel.

A method in a user equipment of an evolved UMTS Terrestrial Radio Access Network, E-UTRAN, operating in time divisional duplex, TDD, mode for performing a random access process, the method comprising:

• receiving on a radio channel a set of bits that represents an extended random access configuration formed from a preamble format and a first random access configuration,
• wherein the first random access configuration comprises a combination of:
• a density value defining a density of random access opportunities on a Physical Random Access Channel, PRACH;
• and
• a version index defining one of several possible patterns of opportunities on the PRACH for that density, each pattern allocating opportunities to different sub-frames of the PRACH;
• jointly decoding the preamble format and the first random access configuration from the set of bits, by determining a value for the preamble format based on the values of all bits in the set and determining a value for the first random access configuration also based on the values of all bits in the set, and
• performing a random access process using the preamble format and the first random access configuration.

A User Equipment of an evolved UMTS Terrestrial Radio Access Network, E-UTRAN, configured to operate in time divisional duplex, TDD, mode, the User Equipment comprising:

• a receiving circuit configured to receive on a radio channel a set of bits that represents an extended random access configuration formed from a preamble format and a first random access configuration,
• the first random access configuration comprising a combination of:
• a density value defining a density of random access opportunities on a Physical Random Access Channel, PRACH;
• and
• a version index defining one of several possible patterns of opportunities on the PRACH for that density, each pattern allocating opportunities to different sub-frames of the PRACH;
• and
• a control circuit configured to:
• jointly decode the preamble format and the first random access configuration from the set of bits, by determining a value for the preamble format based on the values of all bits in the set and determining a value for the first random access configuration also based on the values of all bits in the set, and
• perform a random access process using the preamble format and the random access configuration.