Abstract:
A random access method in a mobile communication system, the random access method for supporting random access with a cell size of about 100 kilometers (km) or more and a power limited terminal, and a preamble structure thereof are provided. While a conventional long term evolution (LTE) random access preamble sequence is reused, a difference in a round-trip delay time between terminals in a large cell area may be compensated. Additionally, since higher power transmission is achieved per bandwidth, a higher link margin may be secured. Also, compatibility with resource scheduling of the conventional LTE may be maintained. Random access may be supported in a large cell, and a preamble structure of a satellite mobile communication may be implemented based on terrestrial LTE.
Abstract:
Provided is a power control and link adaptation method for compensating for a long round trip delay time and slow channel fading in a long term evolution (LTE)-based mobile communication system having a long round trip delay time, similar to a satellite mobile system, the method that may compensate for the long round trip delay time of the satellite mobile system in which a distance between a base station and a terminal is relatively long, when compared to a terrestrial LTE system, support a modulation and coding scheme (MCS) level requested by a terminal, by predicting a channel after the round trip delay time elapses, maintain compatibility within an existing LTE frame, by generating a transmit power control (TPC) instruction for an uplink closed-loop power control, on a frame by frame basis, and compensate for slow channel fading of the satellite mobile system.
Abstract:
Provided is a communication method for downlink transmission with a low peak to average power ratio (PAPR) and compatibility with long-term evolution (LTE)-based downlink transmission in an LTE-based mobile communication system in which the performance degradation may occur due to a high PAPR in multi-carrier transmission caused by non-linearity of a power amplifier in a base station including a satellite, to have the effects of supporting a terminal that reuses an existing terrestrial LTE chipset and a terminal that enables downlink reception with a low PAPR with no collision between the terminals, and of implementing an integrated satellite/terrestrial mobile communication system with a minimum change of an existing mobile communication system to ensure economic efficiency.
Abstract:
In a satellite and terrestrial integrated communication system in which a satellite communication system and a terrestrial communication system share and use an identical frequency band, an interference to a mobile earth station (MES) of the satellite communication system using an identical frequency by an uplink signal transmitted to a base station of the terrestrial communication system by a user equipment (UE) may be mitigated. When a communication of the MES is requested, a satellite communication apparatus to perform resource block (RB) allocation for a satellite communication in the satellite and terrestrial integrated system may include a controller configured to allocate a first RB to the MES, and a communicator configured to transmit a use notification of the first RB to at least one terrestrial base station located in an interference range of an uplink signal of the MES.
Abstract:
A random access method in a mobile communication system, the random access method for supporting random access with a cell size of about 100 kilometers (km) or more and a power limited terminal and a preamble structure thereof are provided. While a conventional long term evolution (LTE) random access preamble sequence is reused, a difference in a round-trip delay time between terminals in a large cell area may be compensated. Additionally, since higher power transmission is achieved per bandwidth, a higher link margin may be secured. Also, compatibility with resource scheduling of the conventional LTE may be maintained. Random access may be supported in a large cell, and a preamble structure of a satellite mobile communication may be implemented based on terrestrial LTE.
Abstract:
Provided is a communication method for downlink transmission with a low peak to average power ratio (PAPR) and compatibility with long-term evolution (LTE)-based downlink transmission in an LTE-based mobile communication system in which the performance degradation may occur due to a high PAPR in multi-carrier transmission caused by non-linearity of a power amplifier in a base station including a satellite, to have the effects of supporting a terminal that reuses an existing terrestrial LTE chipset and a terminal that enables downlink reception with a low PAPR with no collision between the terminals, and of implementing an integrated satellite/terrestrial mobile communication system with a minimum change of an existing mobile communication system to ensure economic efficiency.
Abstract:
Provided is a power control and link adaptation method for compensating for a long round trip delay time and slow channel fading in a long term evolution (LTE)-based mobile communication system having a long round trip delay time, similar to a satellite mobile system, the method that may compensate for the long round trip delay time of the satellite mobile system in which a distance between a base station and a terminal is relatively long, when compared to a terrestrial LTE system, support a modulation and coding scheme (MCS) level requested by a terminal, by predicting a channel after the round trip delay time elapses, maintain compatibility within an existing LTE frame, by generating a transmit power control (TPC) instruction for an uplink closed-loop power control, on a frame by frame basis, and compensate for slow channel fading of the satellite mobile system.