摘要:
A method for allowing a reception end to effectively detect a sequence used for a specific channel of an OFDM communication system, and apparatus for the same are provided. During the sequence transmission, a specific part of a Zadoff-Chu sequence corresponding to the frequency “0” is omitted from a transmitted signal. In addition, first 31 constituent components of the sequence are continuously mapped to frequency resource elements of “−31” to “−1”, and the last 31 constituent components of the sequence are continuously mapped to frequency resource elements of “1” to “31”.
摘要:
A method for establishing RACH transmission to prepare against the frequency offset is disclosed. The method reduces the length of the RACH preamble even if the frequency offset exists, allows the RACH preamble to include a repeated structure (also called an iterative structure) or to use a specific sequence with less affect on the frequency offset, so that the Node-B can easily detect the RACH preamble. If different conditions are established in a high-speed UE and a low-speed UE, an amount of system overheads can be reduced as compared to another case in which an overall RACH condition has been prescribed for only the high-speed UE irrespective of the low-speed UE. And, the method determines whether the user equipment (UE) can estimate its speed according to the aforementioned RACH setup condition, and prescribes a detailed RACH access method according to the determined result.
摘要:
A method and apparatus for requesting uplink resources in a wireless communication system is provided. A user equipment determines whether a scheduling request for requesting uplink resources is triggered. If the scheduling request is triggered, the user equipment transmits a first set of frequency domain sequences and a second set of frequency domain sequences in a subframe.
摘要:
A method for transmitting a random access preamble to a base station at a user equipment (UE) includes generating the random access preamble from a Zadoff-Chu sequence having a length ‘N’ and a root index ‘M’, wherein the random access preamble is defined by a cyclic shift of the Zadoff-Chu sequence and transmitting the generated random access preamble to the base station via a random access channel, wherein the cyclic shift is given by using a variable corresponding to a Doppler shift of one subcarrier spacing, the variable given by using the root index ‘M’, and wherein the cyclic shift is differently given based on whether the variable is smaller than ⅓ of the length ‘N’.
摘要:
A method of transmitting a scheduling request which is used to request a radio resource for uplink transmission includes configuring an uplink control channel for transmission of a scheduling request in a subframe, the subframe comprising two consecutive slots, a slot comprising a plurality of single carrier-frequency division multiple access (SC-FDMA) symbols, the scheduling request being carried by presence or absence of transmission of the uplink control channel, and transmitting the scheduling request on the uplink control channel.
摘要:
A method for establishing a cyclic shift sequence to provide against the frequency offset is disclosed. The method calculates a distance between a channel response position of the sequence and an alias channel response position caused by a frequency offset, calculates the number of cyclic shifts per group according to the calculated distance, and establishes the cyclic shift (CS)-applying interval. This method easily establishes a cyclic shift (CS) interval at a specific location having no overlapping by considering a channel response of a reception (Rx) sequence and an alias location of this reception (Rx) sequence, although a reception (Rx) signal is shifted by a channel delay spreading or a propagation delay irrespective of categories of a domain generating a sequence, so that it can greatly reduce the number of the detection errors and the false alarm rate. And, if a sequence of the cyclic shift (CS) is allocated to a cell having a frequency offset of more than a predetermined level, the present invention can minimize the influence of a frequency offset on a high-mobility cell.
摘要:
Method for generating reference signal sequence using grouping is explained. In this method, base sequences are grouped such that each group contains at least one base sequence of each length, so UE(s) can use various length sequences as a reference signal. And in this method, inter cell interference caused by using various length sequence as a reference signal sequence can be minimized by grouping sequences having the high cross correlation relation.
摘要:
A method for performing a cell search procedure by a user equipment in a wireless communication system includes receiving a primary synchronization signal (PSS), and obtaining a correlation value of the PSS to detect a multimedia broadcast multicast service (MBMS) indicator indicating whether a service is a dedicated MBMS. Accordingly, whether the service is the dedicated MBMS is indicated using a primary synchronization signal or a secondary synchronization signal used in an initial cell search process, and whether the service is the dedicated MBMS can be known without additional complexity. Therefore, cell search of a user equipment can be more effectively performed.
摘要:
A method for transmitting data in a wireless communication system is provided. The method includes: transmitting first data through a radio resource allocated in a unit of a default transmission time interval (TTI) including at least one sub-frame in a frame including a plurality of sub-frames consisting of a plurality of orthogonal frequency division multiplexing (OFDM) symbols; and transmitting second data through a radio resource allocated in a unit of a modified TTI obtained by changing the number of sub-frames included in the default TTI in the frame.
摘要:
A method of mapping a physical resource to a logical resource in a wireless communication system is provided. The method includes: dividing a physical frequency band into at least one frequency partition, wherein each frequency partition is divided into a localized region and a distributed region in a frequency domain; and mapping the at least one frequency partition into at least one logical resource unit, wherein the localized region is directly mapped into the logical resource unit and the distributed region is mapped into the logical resource unit after rearranging subcarriers within the distributed region.