Coherent tracking for FM In-Band On-Channel receivers
    1.
    发明申请
    Coherent tracking for FM In-Band On-Channel receivers 有权
    FM带内在线接收机的相干跟踪

    公开(公告)号:US20050107045A1

    公开(公告)日:2005-05-19

    申请号:US10715582

    申请日:2003-11-18

    申请人: Brian Kroeger

    发明人: Brian Kroeger

    摘要: A method for coherently tracking a radio signal including at least one digitally modulated reference carrier is provided, wherein the method comprises the steps of demodulating the reference carrier to produce complex coherent reference gains, detecting a transient that affects the complex coherent reference gains, and adjusting the complex coherent reference gains in the vicinity of the transient to produce adjusted complex coherent reference gains. The transient can be caused by switching among the antenna elements or impulsive noise. Receivers that process signals in accordance with the method, and a method of estimating noise variance of symbols in a radio signal are also provided.

    摘要翻译: 提供了一种用于相干跟踪包括至少一个数字调制参考载波的无线电信号的方法,其中该方法包括以下步骤:解调参考载波以产生复相干参考增益,检测影响复相干参考增益的瞬态,以及调整 在瞬态附近的复相干参考增益产生调整后的复相干参考增益。 瞬变可以由天线元件之间的切换或脉冲噪声引起。 还提供了根据该方法处理信号的接收机,以及估计无线电信号中符号噪声方差的方法。

    Symbol tracking for AM in-band on-channel radio receivers
    2.
    发明申请
    Symbol tracking for AM in-band on-channel radio receivers 有权
    AM带内在线无线电接收机的符号跟踪

    公开(公告)号:US20070110185A1

    公开(公告)日:2007-05-17

    申请号:US11273099

    申请日:2005-11-14

    IPC分类号: H03D1/24

    CPC分类号: H04L27/2662 H04H20/36

    摘要: A method for symbol tracking in AM in-band on-channel radio receivers comprises the steps of: receiving a stream of time domain samples; assembling a set of the time domain samples equal to a symbol time plus a half symbol delay in response to a symbol timing adjustment value for each symbol period; interpolating the time domain samples; partitioning the interpolated time domain samples into a first group of samples representing half-off symbols and a second group of samples representing on-time symbols; processing the first and second groups of samples to produce the symbol timing adjustment value; and outputting the second group of samples representing on-time symbols at a symbol rate. An apparatus that performs the method is also included.

    摘要翻译: 一种用于AM带内在线无线电接收机中的符号跟踪的方法包括以下步骤:接收时域样本流; 响应于每个符号周期的符号定时调整值,组合一组等于符号时间加上半符号延迟的时域样本; 内插时域样本; 将内插时域样本划分为表示半时间符号的第一组样本和表示准时间符号的第二组采样; 处理第一和第二组样本以产生符号定时调整值; 并以符号率输出表示准时间符号的第二组采样。 还包括执行该方法的装置。

    Method for synchronizing exporter and exciter clocks

    公开(公告)号:US20060209941A1

    公开(公告)日:2006-09-21

    申请号:US11081267

    申请日:2005-03-16

    申请人: Brian Kroeger

    发明人: Brian Kroeger

    IPC分类号: H04B1/38 H04L7/00

    摘要: A method for synchronizing an exciter clock with a modem frame clock in a broadcasting system comprises the steps of receiving a plurality of modem frame pulses that are representative of the start of modem frames of audio signals and data signals, wherein timing of the modem frame pulses is controlled by a modem frame clock, producing an exciter clock signal, counting pulses representative of the exciter clock signal to produce a count representative of timing error of each incoming modem frame pulse, and controlling the exciter clock signal in response to the count. An apparatus that performs the method is also provided.

    Bandwidth reduction of an FM broadcast signal using a baseband precompensation technique

    公开(公告)号:US20060050807A1

    公开(公告)日:2006-03-09

    申请号:US10937619

    申请日:2004-09-09

    申请人: Brian Kroeger

    发明人: Brian Kroeger

    IPC分类号: H04L27/04

    CPC分类号: H04H20/48 H04H20/30 H04H60/07

    摘要: A method of processing a baseband multiplex signal comprises the steps of frequency modulating the baseband multiplex signal to produce a first modulated signal, filtering the first modulated signal to produce a first filtered signal, demodulating the filtered signal to produce a demodulated baseband multiplex signal, correcting the demodulated baseband multiplex signal to reduce or eliminate distortion in a predetermined frequency range of the demodulated baseband multiplex signal to produce a corrected signal, and frequency modulating the corrected signal to produce a second modulated signal. An apparatus that operates in accordance with the method is also provided.

    Peak-to-average power reduction for FM OFDM transmission
    5.
    发明申请
    Peak-to-average power reduction for FM OFDM transmission 有权
    FM OFDM传输的峰均功率降低

    公开(公告)号:US20050169411A1

    公开(公告)日:2005-08-04

    申请号:US10770314

    申请日:2004-02-02

    申请人: Brian Kroeger

    发明人: Brian Kroeger

    IPC分类号: H04L27/26 H04B1/10

    摘要: A method of reducing peak-to-average power ratio in an OFDM signal comprises the steps of modulating a set of subcarriers with a set of data symbol vectors to produce a first modulated signal, limiting the magnitude of the first modulated signal to produce a first limited modulated signal, demodulating the first limited modulated signal to recover distorted input symbol vectors, constraining the distorted input symbol vectors to values greater than or equal to a minimum threshold value to produce constrained data symbol vectors, constraining out-of-band spectral components to lie within a predetermined mask, and remodulating the constrained data symbol vectors. A transmitter that performs the method is also included.

    摘要翻译: 降低OFDM信号中的峰值与平均功率比的方法包括以一组数据符号向量调制一组子载波以产生第一调制信号的步骤,限制第一调制信号的幅度以产生第一 解调第一有限调制信号以恢复失真的输入符号向量,将失真的输入符号向量约束到大于或等于最小阈值的值,以产生受限数据符号向量,将带外频谱分量约束到 位于预定掩码内,并重新调制约束的数据符号向量。 还包括执行该方法的发射机。

    Carrier tracking for AM in-band on-channel radio receivers
    6.
    发明申请
    Carrier tracking for AM in-band on-channel radio receivers 有权
    AM带内在线无线电接收机的载波跟踪

    公开(公告)号:US20070110186A1

    公开(公告)日:2007-05-17

    申请号:US11273396

    申请日:2005-11-14

    IPC分类号: H03D1/24

    摘要: A method for carrier tracking in AM in-band on-channel radio receivers comprises the steps of receiving an input signal, generating a local oscillator signal in response to an oscillator control signal, mixing the input signal with a local oscillator signal to produce a first signal, filtering the first signal to produce a filtered first signal at a decimated sample rate, detecting the phase error and frequency error of the filtered first signal normalized to mitigate effects of signal fades, and using an adaptive loop filter to produce the oscillator control signal in response to the phase error and frequency error of the filtered first signal. An apparatus that performs the method is also provided.

    摘要翻译: 一种用于AM带内在线无线电接收机中的载波跟踪的方法包括以下步骤:接收输入信号,响应于振荡器控制信号产生本地振荡器信号,将输入信号与本地振荡器信号混合以产生第一 信号,对第一信号进行滤波,以抽取采样率产生滤波后的第一信号,检测被滤波后的第一信号的相位误差和频率误差,以便减轻信号衰落的影响,并使用自适应环路滤波器产生振荡器控制信号 响应于滤波的第一信号的相位误差和频率误差。 还提供了执行该方法的装置。

    Equalizer for AM in-band on-channel radio receivers
    7.
    发明申请
    Equalizer for AM in-band on-channel radio receivers 有权
    用于AM带内在线无线电接收机的均衡器

    公开(公告)号:US20070110020A1

    公开(公告)日:2007-05-17

    申请号:US11272978

    申请日:2005-11-14

    IPC分类号: H04J1/00

    摘要: A method is provided for equalizing OFDM symbol vectors received on AM in-band on-channel radio signal including a main carrier and first and second BPSK modulated subcarriers. The method comprises the steps of: computing a BPSK magnitude signal; filtering the BPSK magnitude signal; filtering complex samples received on the main carrier; using the filtered BPSK magnitude signal and the filtered complex samples received on the main carrier to compute a plurality of flat fade equalization coefficients; and multiplying the OFDM symbol vectors by the flat fade equalization coefficients. A receiver that includes an equalizer, which operates in accordance with the method is also provided.

    摘要翻译: 提供了一种用于均衡在包括主载波和第一和第二BPSK调制副载波的AM带通上信道无线电信号上接收的OFDM符号向量的方法。 该方法包括以下步骤:计算BPSK幅度信号; 滤波BPSK幅度信号; 过滤在主载波上接收的复杂样本; 使用滤波的BPSK幅度信号和在主载波上接收的经滤波的复数样本来计算多个平坦衰落均衡系数; 并且将OFDM符号向量乘以平坦衰落均衡系数。 还提供了包括根据该方法操作的均衡器的接收器。

    Method for alignment of analog and digital audio in a hybrid radio waveform
    8.
    发明申请
    Method for alignment of analog and digital audio in a hybrid radio waveform 有权
    在混合无线电波形中对准模拟和数字音频的方法

    公开(公告)号:US20060227814A1

    公开(公告)日:2006-10-12

    申请号:US11101795

    申请日:2005-04-08

    IPC分类号: H04J3/06

    摘要: This invention provides a method of detecting time alignment of an analog audio signal and a digital audio signal in a hybrid radio system. The method comprises the steps of filtering the analog audio signal to produce a filtered analog audio signal, filtering the digital audio signal to produce a filtered digital audio signal, and using the filtered analog audio signal and the filtered digital audio signal to calculate a plurality of correlation coefficients, wherein the correlation coefficients are representative of time alignment between the analog audio signal and the digital audio signal. An apparatus for performing the method is also provided.

    摘要翻译: 本发明提供了一种在混合无线电系统中检测模拟音频信号和数字音频信号的时间对准的方法。 该方法包括以下步骤:对模拟音频信号进行滤波以产生经滤波的模拟音频信号,对数字音频信号进行滤波以产生经滤波的数字音频信号,并使用滤波后的模拟音频信号和滤波后的数字音频信号来计算多个 相关系数,其中相关系数表示模拟音频信号和数字音频信号之间的时间对准。 还提供了一种用于执行该方法的装置。

    Method and apparatus for blending an audio signal in an in-band on-channel radio system

    公开(公告)号:US20060019601A1

    公开(公告)日:2006-01-26

    申请号:US10898829

    申请日:2004-07-26

    IPC分类号: H04H7/00

    摘要: A method for processing a composite digital audio broadcast signal to mitigate intermittent interruptions in the reception of the digital audio broadcast signal, the method comprising the steps of separating an analog audio portion of the digital audio broadcast signal from a digital audio portion of the digital audio broadcast signal, detecting errors in the digital audio portion of the digital audio broadcast signal, adjusting the digital audio portion of the digital audio broadcast signal in response to errors in the digital audio portion of the digital audio broadcast signal to produce an adjusted digital audio portion, and blending the analog audio portion with the adjusted digital audio portion to produce an audio output. A receiver that performs the method is also included.

    Forward error correction coding for hybrid AM in-band on-channel digital audio broadcasting systems
    10.
    发明申请
    Forward error correction coding for hybrid AM in-band on-channel digital audio broadcasting systems 有权
    用于混合AM带内同频数字音频广播系统的前向纠错编码

    公开(公告)号:US20050163256A1

    公开(公告)日:2005-07-28

    申请号:US10764629

    申请日:2004-01-26

    申请人: Brian Kroeger

    发明人: Brian Kroeger

    摘要: An AM compatible digital audio broadcasting signal comprises an analog modulated carrier signal centrally positioned in a radio channel, wherein the analog modulated carrier signal is modulated by an analog signal, and a plurality of digitally modulated subcarrier signals in the radio channel, wherein the digitally modulated subcarrier signals are modulated using complementary pattern-mapped trellis code modulation including a code mapped to overlapping partitions. Time diversity can be included between the analog modulated carrier signal and the plurality of digitally modulated subcarrier signals, and/or between groups of the digitally modulated subcarrier signals. A broadcasting method, and transmitters and receivers and that utilize the signal are also provided.

    摘要翻译: AM兼容数字音频广播信号包括集中位于无线电信道中的模拟调制载波信号,其中模拟调制载波信号由无线电信道中的模拟信号和多个数字调制副载波信号调制,其中数字调制 使用包括映射到重叠分区的代码的互补模式映射网格码调制来调制副载波信号。 时间分集可以包括在模拟调制载波信号和多个数字调制副载波信号之间和/或数字调制副载波信号的组之间。 还提供了一种广播方法,以及发射机和接收机以及利用该信号。