Method and apparatus for extending coverage in communication system
摘要
說明書
The actual PUSCH instance may always have a DM-RS. This operation may help the base station to ensure a quality of channel estimation in a step of receiving data. For example, the base station may estimate a channel by performing a joint estimation operation, and may perform a reception operation of contiguous actual PUSCH instances based on the estimated channel. When a DM-RS is mapped to a PUSCH instance, there may be few symbols to which data is mapped in the corresponding PUSCH instance. In order to solve this problem, the following methods may be considered.
Method 2.3-9: A DM-RS may not be mapped to some PUSCH instances. When the number of symbols allocated for data among symbols of a PUSCH instance is small, an effective code rate may be greater than or equal to a predefined threshold. In this case, the DM-RS may be dropped, and data may be mapped to the PUSCH instance instead of the DM-RS.
In order to determine whether to allocate a DM-RS, the terminal may assume that a DM-RS is virtually allocated, and may calculate a code rate based on the above-mentioned assumption. When the calculated code rate is greater than or equal to a threshold defined in the technical specification (e.g., effective code rate=0.95), the terminal may not allocate a DM-RS to the PUSCH instance. After determining whether to allocate a DM-RS, the terminal may map coded symbols (e.g., modulation symbols) of the data to a resource grid.
2.4 Methods for Enhancement in Power Control
The same transmit power control (TPC) command may be applied to all PUSCH instance(s) belonging to a PUSCH occasion. Since the number of symbols of each PUSCH instance may vary, the PUSCH instances may not have the same transmit power.
