120results about How to "Backward Compatibility Guaranteed" patented technology

A method for uplink transmission in an OFDMA system is provided. The subcarrier transmission method includes arranging 4 pilot REs at different positions of a frequency axis in a basic unit when the basic unit includes 4 subcarriers on the frequency axis and 6 OFDM(A) symbols in a time axis, arranging data REs at remaining positions of the basic unit, and transmitting the basic unit to a receiving end.

The invention provides a method for implementing an uplink synchronization HARQ (Hybrid Automatic Repeat Request) process in a multi-base station cooperative receiving network. In the method, according to a specific embodiment, a service base station provides a receiving response according to a response time limit for an uplink synchronization HARQ process with a smaller response time limit and formally directs a terminal to retransmit or start a new transmission after finishing the combination. According to another embodiment, the uplink synchronization HARQ process has a response time limitmatched with the time delay of the multi-base station receiving network so that the service base station sends a receiving response or a control signaling on a PDCCH (Packet Dedicated Control Channel) after finishing the combination. Thus uplink synchronization HARQ in a multi-base station cooperative receiving environment in LTE (Long Term Evolution) and LTEA (LTE-Advanced) networks can be realized.

When a wavelength having the same value as a reference wavelength λ1 of a first laser light is set to a designed wavelength λ, a diffractive optical element has: an inner circular side irregular diffraction pattern portion, in which a plurality of irregular portions in which a height of a convex portion is set to approximately 1λ-fold of the designed wavelength λ with respect to a concave portion are repeated, being formed in an annular shape in an inner circular area having a predetermined diameter for the correction of a spherical aberration generated due to a difference in substrate thickness between first and second optical recording mediums centering on a central point through which an optical axis runs while gradually changing a pitch of the irregular portions in a radial direction toward the outer circular side; and an outer circular side tiered diffraction pattern portion which is intended to improve a chromatic aberration with respect to the first laser light by forming in an annular shape in an outer circular area outside the inner circular side irregular diffraction pattern portion a plurality of tiers by setting a height of each tier to approximately mλ-fold (where m is a natural number which does not include 0) of the designed wavelength λ or by setting the same while changing a value of m for each tier.

First and second phase function curves are respectively obtained based on first and second phase functions with a wavelength having the same value as a reference wavelength λ1 of a first laser light being determined as a designed wavelength λ, a phase shift element then has an inner circular side tiered phase difference pattern portion formed in annular shapes in an inner circular area on one surface thereof based on the first phase function curve and an outer circular side tiered phase difference pattern portion formed in annular shapes in an outer circular area outside the inner circular side tiered phase difference pattern portion based on the second phase function curve. A tier pitch of tiers of the inner circular side tiered phase difference pattern portion is set to a height corresponding to a phase difference of approximately 1λ and, on the other hand, a tier pitch of tiers of the outer circular side tiered phase difference pattern portion is set to a height corresponding to a phase difference of approximately mλ (where m is a natural number which does not include 0) or a height corresponding to a phase difference of approximately mλ by changing a value of m in accordance with each tier.