Method and device in communication nodes used for random access in wireless communications

A second communication node used for wireless communications, comprising:

• a second transmitter, transmitting first information;
• a third receiver, receiving a first radio signal;
• and
• a third transmitter, transmitting a first-type signaling in a first time window;
• wherein:
• an end time for a transmission of the first radio signal is used for determining a start of the first time window, the end time for a transmission of the first radio signal is earlier than the start of the first time window;
• time-domain resource(s) occupied by the first radio signal is(are) used for determining a first characteristic identity;
• the first characteristic identity is one of M characteristic identities, M being a positive integer greater than 1;
• the first information is used for determining the M characteristic identities;
• the first-type signaling carries one of the M characteristic identities;
• a transmitter of the first radio signal determines a characteristic identity carried by the first-type signaling out of the M characteristic identities through blind detection;
• any of the M characteristic identities is an RNTI equal to a hexadecimal integer through FFF0 and FFFD;
• and
• the first-type signaling is transmitted through a PDCCH, the monitoring on the first-type signaling is performed in common search space (CSS).

A method in a first communication node used for wireless communications, comprising:

• receiving first information;
• transmitting a first radio signal;
• and
• monitoring a first-type signaling in a first time window;
• wherein:
• an end time for a transmission of the first radio signal is used for determining a start of the first time window, the end time for a transmission of the first radio signal is earlier than the start of the first time window;
• time-domain resource(s) occupied by the first radio signal is(are) used for determining a first characteristic identity;
• the first characteristic identity is one of M characteristic identities, M being a positive integer greater than 1;
• the first information is used for determining the M characteristic identities;
• the first-type signaling carries one of the M characteristic identities;
• the first communication node determines a characteristic identity carried by the first-type signaling out of the M characteristic identities through blind detection;
• any of the M characteristic identities is an RNTI equal to a hexadecimal integer through FFF0 and FFFD;
• and
• the first-type signaling is transmitted through a PDCCH, the monitoring on the first-type signaling is performed in common search space (CSS).