摘要:
TDS-OFDM can be applied to uplink wireless communication multiple accesses through sub-channelization, which means that each user uses a portion of available bandwidth to achieve orthogonal multiple access, where the sub-carriers in each sub-band may be contiguous or distributed. Inside the bandwidth for each user, at least one random or known sequence is used as the guard interval between transmitted symbols, where the sequence is limited inside the sub-band.
摘要:
In a TDS-OFDM system, frequency offset estimate provided. A method for estimating a frequency offset comprising the step of correlating a known PN sequence with a received signal.
摘要:
In a TDS-OFDM system, a method for transmission is provided. The method comprises the step of: adjusting a PN sequence length, whereby a required performance is maintained. The adjusting step comprises increasing, decreasing, or keep unchanging the PN sequence length.
摘要:
A channel estimation using the received PN (pseudo-noise) sequence associated with a received frame among a plurality of associated, neighboring frames. The estimation using a value associated with a point of a currently frame as a denominator in a predetermined formula. If the value is smaller than its corresponding value in a neighboring frame, the neighboring frame's corresponding value is used instead of the value of the current frame.
摘要:
A device for equalization adapted for receiving a symbol and a channel frequency response is provided. The device includes a slicer for delimiting the channel frequency response to a sliced channel frequency response based upon a signal constellation; and a divider for dividing the received symbol using the sliced channel frequency response as the divider, with a resultant quotient of the divider as a reference point for future received symbols.
摘要:
Systems, methods and apparatus are provided through which heat produced in the patient examination space by the power used to create electromagnetic fields in an MRI/MRS system is significantly reduced by coolant carried by one of two split connected concentric coil layers of one of two of the primary gradient coils used to alter the main magnetic field. The coil carrying the coolant is made of copper tubing. The second primary gradient coil is placed between the layers of the split primary gradient coil. Adjusting the number of turns in each layer of the split primary gradient coil adjusts the heat generated. The inductances and resistances of the two primary gradient coils are balanced by adjusting the gain of the coils.
摘要:
Method and system for determining whether one or more multipath signals is present in a received signal frame that includes a reference symbol (RS) sequence RS(t;m1) as part of the frame, and for iteratively evaluating a multipath signal that is present. The RS sequence index (m1) for the frame is identified, and first and second Fourier transforms Φ(f;m1;ref) and Φ(f;rec) for the received frame are provided for a selected time segment IS that includes the RS sequence of the received frame. An inverse Fourier transform σ(t;m1) of the ratio of the transforms is computed and analyzed. If at least one multipath signal is present, σ(t;m1) is nonlinearly filtered, and the filtered function is convolved with RS(t;m1). This convolution represents a received signal extension, due to multipath signal(s) presence. A refinement procedure analyzes a contribution to multipath signals from the preceding frame(s). The procedure is iteratively driven toward an optimal representation of any multipath signal(s) present.
摘要翻译:用于确定在包括作为帧的一部分的参考符号(RS)序列RS(t; m 1)的接收信号帧中是否存在一个或多个多径信号的方法和系统,并且用于迭代地评估存在的多径信号 。 识别该帧的RS序列索引(m 1),并且为所选择的时间段IS提供接收帧的第一和第二傅里叶变换Phi(f; m 1; ref)和Phi(f; rec) 接收帧的RS序列。 计算和分析变换比率的傅立叶逆变换Σ(t; m 1)。 如果存在至少一个多径信号,则σ(t; m 1)被非线性滤波,滤波后的函数与RS(t; m 1)卷积。 由于多路径信号存在,该卷积表示接收到的信号扩展。 细化程序分析对来自前一帧的多路径信号的贡献。 该过程被迭代地驱动到存在的任何多径信号的最佳表示。
摘要:
An alignment layer is provided over liquid crystals for a display. Alignment marks are laser-written on the alignment layer, such that the liquid crystals become aligned with one another.
摘要:
A process for creating and an apparatus employing shaped orifices in a semiconductor substrate. A first layer of material is applied on the semiconductor substrate then a second layer of material is then applied upon the first layer of material. An orifice image is then transferred to the first layer of material and a fluid-well image is transferred to the second layer of material. That portion of the second layer of material where the orifice image is located is then developed along with that portion of the first layer of material where the fluid well is located to define an orifice in the substrate.
摘要:
MRI operates by passing current through gradient coils to create a magnetic field. Creation of the magnetic field requires a relatively high current which causes a large heat build up within the MRI, especially in the patient space. The present invention provides for a hollow conductor through which a coolant can be passed directly during the application of current.