专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明授权

US06392988B1 Transmitter architecture employing space time spreading and orthogonal transmit diversity techniques 有权
标题翻译：采用时空扩展和正交发射分集技术的发射机架构
公开(公告)号：US06392988B1
公开(公告)日：2002-05-21
申请号：US09394172
申请日：1999-09-13
申请人： Stephen Alan Allpress , R. Michael Buehrer , Quinn Li , Nallepilli S. Ramesh , Robert Atmaram Soni
发明人： Stephen Alan Allpress , R. Michael Buehrer , Quinn Li , Nallepilli S. Ramesh , Robert Atmaram Soni
IPC分类号： H04J1100
CPC分类号： H04L1/0618
摘要： Disclosed is a common transmitter architecture having incorporated both open loop transmit diversity schemes using a plurality of binary switches. Employment of binary switches allows for the sharing of certain components whether the transmitter is utilizing a orthogonal transmit diversity (OTD) scheme or a space time spreading (STS) scheme. Accordingly, the number of components in the transmitter is minimized and the complexity of the transmitter is simple enough to be implemented into a single application specific integrated chip.
摘要翻译：公开了一种共同的发射机架构，其结合了使用多个二进制交换机的开环发射分集方案。二进制交换机的使用允许某些组件的共享，无论发射机是利用正交发射分集（OTD）方案还是空间时间扩展（STS）方案。因此，发射机中的组件数量被最小化，并且发射机的复杂性足够简单以被实现到单个专用集成芯片中。

2. 发明授权

US5956345A IS-95 compatible wideband communication scheme 失效
标题翻译： IS-95兼容宽带通信方案
公开(公告)号：US5956345A
公开(公告)日：1999-09-21
申请号：US712831
申请日：1996-09-13
申请人： Stephen Alan Allpress , Nallepilli S. Ramesh
发明人： Stephen Alan Allpress , Nallepilli S. Ramesh
IPC分类号： H04L27/20 , H04B1/69 , H04L5/02 , H04B7/216 , H04B7/208 , H04J13/00
CPC分类号： H04B1/69 , H04L5/026
摘要： A plurality of modulated signals are generated for a data stream. Each modulated signal, which contains all of the information in the data stream, is generated at a different carrier frequency. The modulated signals are combined for transmission as a multi-band signal. In one embodiment, the modulated signals are compatible with signals generated in accordance with the IS-95 telecommunications standard. According to this embodiment, wideband data streams are combined with code sequences that are based on the same Walsh code sequences used to generate IS-95 signals. Each wideband data stream is encoded using either a particular Walsh code sequence or its logical negation to generate one coded stream for each carrier frequency used to generate the IS-95 signals. Each coded stream is then modulated at one of the carrier frequencies using spread-spectrum modulation to generate one of a plurality of modulated signals for that wideband data stream, where each modulated signals contains all of the information in the original wideband data stream. Through systematic assignment of Walsh code sequences and their logical negations, and through appropriate spread-spectrum modulation of the wideband data, the resulting multi-band modulated signal for each wideband data stream is assured of being orthogonal to all other such multi-band modulated signals, as well as orthogonal to every IS-95 signal. As such, the invention increases both the user and data-rate capacities of an IS-95 network without requiring any additional carrier frequencies or code sequences beyond those already supported by the IS-95 network.
摘要翻译：为数据流生成多个调制信号。包含数据流中的所有信息的每个调制信号以不同的载波频率生成。调制信号被组合以作为多频带信号进行传输。在一个实施例中，调制信号与根据IS-95电信标准产生的信号兼容。根据本实施例，宽带数据流与基于用于产生IS-95信号的相同沃尔什码序列的码序列组合。使用特定沃尔什码序列或其逻辑否定来对每个宽带数据流进行编码，以生成用于生成IS-95信号的每个载波频率的一个编码流。然后使用扩频调制在一个载波频率上对每个编码流进行调制，以产生用于该宽带数据流的多个调制信号之一，其中每个调制信号包含原始宽带数据流中的所有信息。通过Walsh码序列及其逻辑否定的系统分配，并通过对宽带数据进行适当的扩频调制，确保每个宽带数据流的结果多频带调制信号与所有其他这样的多频带调制信号正交，以及与每个IS-95信号正交。因此，本发明增加了IS-95网络的用户和数据速率容量，而不需要除了IS-95网络已经支持的任何附加载波频率或代码序列。

3. 发明授权

US06643280B1 Method and apparatus for generation of CDMA long codes 有权
标题翻译：用于生成CDMA长码的方法和装置
公开(公告)号：US06643280B1
公开(公告)日：2003-11-04
申请号：US09428513
申请日：1999-10-27
申请人： Quinn Li , Nallepilli S. Ramesh
发明人： Quinn Li , Nallepilli S. Ramesh
IPC分类号： H04B7216
CPC分类号： H04B1/70756 , H04J13/10
摘要： A long code generator is disclosed that maintains a common long code state between a system with multiple spreading rates, such as a spreading rate equal to the chip rate (1×) and a spreading rate at a multiple of the chip rate (n×), such as three-times the chip rate (3×). An n× long code generator generates n bits for every clock pulse, where the clock operates at the system chip rate. n bits are generated for every clock period by having the long code mask value assume n values for each clock period. Thus, the long code mask value is changed at n times the chip rate, while the shift register is operated at the chip rate. Each of the long codes corresponding to the n long code mask values are multiplexed, for example, using an interlacing technique. The long code generator includes a conventional shift register, AND gate array, modulo-2 adder and clock. In addition, the disclosed long code generator includes a novel long code mask generator that generates n long code masks for each clock period. The long code mask generator operates with a chip rate of n-times the system clock (n×1.2288 MHz). The three long code masks generated for each user must be different from one another, and different from the three long code masks generated for all other users. All the randomness properties necessary for proper CDMA operation are preserved. The present invention applies to both the forward and reverse links for long code generation. Long code state synchronization is maintained between two systems employing different spreading rates, thereby facilitating handoffs without explicit messaging of state information.
摘要翻译：公开了一种长码发生器，其在具有多个扩展速率的系统（例如等于码片速率（1x）的扩展速率）和码片速率（nx）的倍数处的扩展速率的情况下维持公共长码状态，作为芯片速率的三倍（3倍）。 nx长码发生器为每个时钟脉冲产生n位，其中时钟以系统码片速率工作。通过使每个时钟周期的长码掩码值为n个值，为每个时钟周期生成n位。因此，长码掩码值以码片速率的n倍改变，而移位寄存器以码片速率运行。对应于n个长码屏蔽值的长码中的每一个例如使用隔行扫描技术进行复用。长码发生器包括常规移位寄存器AND门阵列，模2加法器和时钟。此外，所公开的长码发生器包括一个新的长码掩码生成器，其在每个时钟周期产生n个长码掩码。长码掩码生成器以芯片速率为n倍系统时钟（nx1.2288 MHz）。为每个用户生成的三个长代码掩码必须彼此不同，并且与为所有其他用户生成的三个长代码掩码不同。保持适当CDMA操作所需的所有随机性。本发明适用于长码产生的前向链路和反向链路两者。在采用不同扩展速率的两个系统之间维持长码状态同步，从而便于无需状态信息的显式消息传递的切换。

4. 发明授权

US06389138B1 Method and apparatus for generating a complex scrambling code sequence 有权
标题翻译：用于生成复杂扰码序列的方法和装置
公开(公告)号：US06389138B1
公开(公告)日：2002-05-14
申请号：US09190195
申请日：1998-11-12
申请人： Quinn Li , Nallepilli S. Ramesh
发明人： Quinn Li , Nallepilli S. Ramesh
IPC分类号： H04K100
CPC分类号： H04J13/10 , H04B1/707
摘要： A complex spreading and/or scrambling code sequence generation system uses a first complex code sequence having at least two components and a second complex code sequence having at least two components. The components of the first complex code sequence are respectively mixed with the corresponding components of the second complex code sequence to generate the complex scrambling code sequence. In doing so, an offset between the components of the complex scrambling code sequence is achieved for the same and/or different users. The complex scrambling code sequence can be used for spreading, scrambling, de-spreading or descrambling an information signal.
摘要翻译：复扩展和/或扰码编码序列生成系统使用具有至少两个分量的第一复编码序列和具有至少两个分量的第二复编码序列。第一复编码序列的分量分别与第二复码序列的对应分量混合以产生复数扰码序列。在这样做时，为相同和/或不同的用户实现了复杂扰码序列的分量之间的偏移。复数扰码序列可用于扩展，加扰，解扩或解扰信息信号。

5. 发明授权

US06721339B2 Method of providing downlink transmit diversity 有权
标题翻译：提供下行链路发射分集的方法
公开(公告)号：US06721339B2
公开(公告)日：2004-04-13
申请号：US09375598
申请日：1999-08-17
申请人： Quinn Li , Nallepilli S. Ramesh
发明人： Quinn Li , Nallepilli S. Ramesh
IPC分类号： H04B700
CPC分类号： H04L1/0071 , H04B1/707 , H04B7/06 , H04B7/12 , H04J13/18 , H04L1/004 , H04L1/04 , H04L1/06
摘要： A transmitter for wireless communications provides multiple types of orthogonality to improve transmit diversity. Transmit diversity is improved by using both coding and carrier frequency orthogonality. Data to be transmitted is broken into four parallel channels. Two of the channels are transmitted on a first carrier signal and the other two channels are transmitted on a second carrier signal. Channels transmitted on the same carrier signal are provided with orthogonal codes so that they may be separated by a receiver. Channels transmitted on different carrier signals may be encoded with identical orthogonal codes. The modulated carrier signals are then transmitted using at least two antennas, where one antenna is used for each carrier.
摘要翻译：用于无线通信的发射机提供多种类型的正交性以改善发射分集。通过使用编码和载波频率正交性来改善发射分集。要发送的数据被分解为四个并行通道。两个信道在第一载波信号上发送，另外两个信道在第二载波信号上发送。在相同载波信号上发送的信道被提供有正交码，使得它们可以被接收机分离。在不同载波信号上发送的信道可以用相同的正交码进行编码。然后使用至少两个天线发送调制的载波信号，其中每个载波使用一个天线。

6. 发明授权

US4737722A Serial port synchronizer 失效
标题翻译：串口同步器
公开(公告)号：US4737722A
公开(公告)日：1988-04-12
申请号：US759623
申请日：1985-07-26
申请人： Nallepilli S. Ramesh , Subramanian Narasimhan
发明人： Nallepilli S. Ramesh , Subramanian Narasimhan
IPC分类号： H04J3/06 , H03K5/00 , H03L7/00 , H04L7/02 , H04L7/033 , H04L7/04 , H04M11/00 , H03K1/17 , H03K5/13 , H03K17/00
CPC分类号： H04L7/0331
摘要： Method and apparatus for rapid, low-jitter acquisition of a clock signal at a serial communication port. In the absence of communication over the port, and during clock acquisition, a free-running clock is generated for local communication. Following clock acquisition by a circuit which performs coarse phase adjustments, a simple logic network generates refined phase adjustment signals which drive a variable, nominal divide-by-32, counter so that the clock generated thereby is smoothly brought into synchronization with the acquired clock in one bit increments. In a typical application, at most 48 bit periods at the port are required to synchronize the clock, with a clock phase jitter of less than 1.1%.
摘要翻译：用于在串行通信端口快速，低抖动地采集时钟信号的方法和装置。在端口没有通信的情况下，在时钟采集期间，为本地通信生成一个自由运行的时钟。在通过执行粗调相位调整的电路进行时钟采集之后，简单的逻辑网络产生精细的相位调整信号，其驱动可变的标称除以32的计数器，使得由此产生的时钟平滑地与所获取的时钟同步一位增量。在典型应用中，端口最多需要48位周期才能同步时钟，时钟相位抖动小于1.1％。

7. 发明授权

US5493712A Fast AGC for TDMA radio systems 失效
标题翻译：用于TDMA无线电系统的快速AGC
公开(公告)号：US5493712A
公开(公告)日：1996-02-20
申请号：US216371
申请日：1994-03-23
申请人： Nallepilli S. Ramesh , Krishnamurthy Sreenath
发明人： Nallepilli S. Ramesh , Krishnamurthy Sreenath
IPC分类号： H03G3/20 , H04B1/06
CPC分类号： H03G3/3047
摘要： Disclosed is a circuit for automatic gain control (AGC) of random access channels (RACH) and traffic channels in a radio system. The amplitude of the input signal is detected at an intermediate frequency (IF) stage, digitized, and coupled to a digital signal processor (DSP) which produces an AGC signal for reducing the gain of the input when the input crosses a threshold value. For RACH bursts, the AGC signal tracks the input signal when it crosses the threshold and the AGC signal remains at a constant value for the the remainder of the time slot unless and until the input increases a threshold amount over its previous highest value. For traffic channels, the DSP will use the AGC signal from the RACH burst as an initial value and change the AGC signal only if the detected input is outside a predetermined range.
摘要翻译：公开了一种用于无线电系统中随机接入信道（RACH）和业务信道的自动增益控制（AGC）的电路。输入信号的幅度在中频（IF）级被检测，数字化并耦合到数字信号处理器（DSP），数字信号处理器（DSP）产生AGC信号，用于当输入跨越阈值时降低输入的增益。对于RACH突发，当AGC信号越过阈值时，AGC信号跟踪输入信号，并且AGC信号在时隙的其余部分保持恒定值，除非和直到输入增加超过其先前最高值的阈值。对于业务信道，DSP将使用来自RACH脉冲串的AGC信号作为初始值，并且仅当检测到的输入在预定范围之外时才改变AGC信号。

8. 发明授权

US5805567A Orthogonal modulation scheme 失效
公开(公告)号：US5805567A
公开(公告)日：1998-09-08
申请号：US712832
申请日：1996-09-13
申请人： Nallepilli S. Ramesh
发明人： Nallepilli S. Ramesh
IPC分类号： H04L27/20 , H04J11/00 , H04J13/00 , H04L5/12 , H04B7/216
CPC分类号： H04J13/0048 , H04L5/12
摘要： The modulation scheme has two versions that can transform two data streams into two mutually orthogonal modulated signals within the same carrier-frequency band. In one embodiment, the modulation scheme is a quadrature-phase shift-keying (QPSK) modulation scheme having an in-phase part and a quadri-phase part. In this embodiment, one version of the QPSK modulation scheme conforms to the IS-95 telecommunications standard. In this version, the in-phase part is applied to a first data stream to generate an in-phase signal that is multiplied by a cosine function of the carrier frequency. In a parallel path, the quadri-phase part is applied to the first data stream to generate a quadri-phase signal that is multiplied by a sine function of the carrier frequency. The resulting signals are combined to generate a conventional IS-95 signal. In this embodiment, the other version of the QPSK modulation scheme is designed to transform a second data stream into a second modulated signal that is orthogonal to the IS-95 signal, even though the second modulated signal is within the same carrier-frequency band and even if the second data stream is encoded using the same Walsh code sequence as the first data stream. In one implementation of the second version, the logical negation of the quadri-phase part of the QPSK modulation scheme is applied to the second data stream to generate an quadri-phase signal that is multiplied by the cosine function of the carrier frequency. In a parallel path, the in-phase part of the QPSK modulation scheme is applied to the second data stream to generate an in-phase signal that is multiplied by the sine function of the carrier frequency. The resulting signals are combined to generate a modulated signal that is orthogonal to the IS-95 signal and which therefore will not interfere with the IS-95 signal, even though the two modulated signals exist within the same carrier-frequency band and may in fact be based on two data streams that were encoded using the same Walsh code sequence. Those skilled in the art will understand that the modulation scheme of the present invention can be implemented in contexts other than the IS-95 standard.

9. 发明授权

US4879727A Adaptive threshold sampling controller 失效
标题翻译：自适应阈值采样控制器
公开(公告)号：US4879727A
公开(公告)日：1989-11-07
申请号：US904540
申请日：1986-09-05
申请人： Nallepilli S. Ramesh , Suresh Cheemalavagu , Anders Erikson
发明人： Nallepilli S. Ramesh , Suresh Cheemalavagu , Anders Erikson
IPC分类号： H04J3/00 , H03K5/08 , H04L5/14 , H04L25/02 , H04L25/03 , H04L25/12 , H04Q5/00 , H04Q11/04
CPC分类号： H04Q11/0428 , H03K5/082 , H04L25/12 , H04L5/1492 , H04L25/0272
摘要： A method of sampling marks on a transmission line and adjusting their peak amplitude to compensate for attenuation of signal strength on the line and of "voltage addition" caused by multiple terminals transmitting on the line. For networks meeting the CCITT I-Series Recommendation, two B-channels and a D-channel are transmitted in frames over the line; the B-channel forming the best basis for threshold adaptation, the D-channel the next best basis and the F-bit preceeding each frame used in the absence of either B- or D-channel signals. Accordingly, a B-bit mark sample is taken if possible, otherwise a D-bit mark sample; or if neither is present an F-bit mark sample; the adaptive threshold preferably being set at 55% of the peak value of the sample. The method is readily implemented as a "state machine" and consequently can be constructed from a programmable logic array.
摘要翻译：一种在传输线上采样标记并调整其峰值幅度以补偿线路上的信号强度的衰减和由线路上发送的多个终端引起的“电压相加”的方法。对于符合CCITT I系列建议书的网络，两个B信道和D信道以帧为单位传输; B信道形成阈值适配的最佳基础，D信道是下一个最佳基础，并且在没有B信道或D信道信号的情况下使用的每个帧之前的F位。因此，如果可能，采取B位标记样品，否则D位标记样品; 或者既不存在F位标记样品; 优选地将自适应阈值设置为样品的峰值的55％。该方法很容易实现为“状态机”，因此可以由可编程逻辑阵列构成。

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式