The use of space-time coded ARTM continuous phase modulation to solve the two-antenna problem in aeronautical mobile telemetry requires estimates of the parameters that define the propagation environment. The maximum likelihood estimator problem is defined and used to motivate reduced-complexity estimators suitable for use in a real system. A modified gradient descent algorithm performs the search required to find the delay parameters. An “inner” phase-lock loop operating with an “outer” frequency-lock loop computes decision-directed estimates of the frequency offset. Computer simulations were used to assess the impact on bit error rate performance introduced by the estimators. The simulation results show that the combined joint estimator for the delays, channel gains, and frequency offset imposes a 1.15-dB loss in performance.

中文翻译：

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航空移动遥测中时空分组编码 ARTM CPM 估计器


使用空时编码ARTM连续相位调制来解决航空移动遥测中的双天线问题需要对定义传播环境的参数进行估计。定义最大似然估计器问题并用于激发适合在实际系统中使用的降低复杂度的估计器。改进的梯度下降算法执行查找延迟参数所需的搜索。与“外部”锁频环一起操作的“内部”锁相环计算频率偏移的决策引导估计。使用计算机模拟来评估估计器对误码率性能的影响。仿真结果表明，延迟、信道增益和频率偏移的组合联合估计器造成 1.15 dB 的性能损失。