Smart antennas for combined DOA and joint channel estimation in time-slotted CDMA mobile radio systems with joint detection

Abstract-We derive Cramér-Rao bound (CRB) expressions for the range (time delay), velocity (Doppler shift), and direction of a point target using an active radar or sonar array. First, general CRB expressions are derived for a narrowband signal and array model and a space-time separable noise model that allows both spatial and temporal correlation. We discuss the relationship between the CRB and ambiguity function for this model. Then, we specialize our CRB results to the case of temporally white noise and the practically important signal shape of a linear frequency modulated (chirp) pulse sequence. We compute the CRB for a three-dimensional (3-D) array with isotropic sensors in spatially white noise and show that it is a function of the array geometry only through the "moments of inertia" of the array. The volume of the confidence region for the target's location is proposed as a measure of accuracy. For this measure, we show that the highest (and lowest) target location accuracy is achieved if the target lies along one of the principal axes of inertia of the array. Finally, we compare the location accuracies of several array geometries.

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“…VI]). Interestingly, it has also been recently proposed to model noise and interference in wireless communication systems [13].…”

Section: Signal and Noise Modelsmentioning

confidence: 99%

Cramer-Rao bounds for estimating range, velocity, and direction with an active array

Dogandzic

Nehorai

2001

IEEE Trans. Signal Process.

190

111

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“…Compared to other 3G CDMA systems, the main features of TD-SCDMA are the utilization of smart antennas and joint detection receiver [2]. However, both the aforementioned key technologies are highly dependent on the accuracy of channel estimation (CE) [3] [4]. Consequently, to guarantee the performance of TD-SCDMA systems, it is desirable to develop a CE algorithm with high precision and low complexity.…”

Section: Introductionmentioning

confidence: 99%

High Precision Multi-cell Channel Estimation Algorithm Based on Successive Interference Cancellation

Wen

Cheng

et al. 2011

2011 Third International Conference on Communications and Mobile Computing

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This paper proposes a novel multi-cell channel estimation algorithm based on successive interference cancellation (SIC) for Time Division Synchronization Code Division Multiple Access (TD-SCDMA) systems. Unlike existing interference cancellation (IC) schemes, where the interference reconstruction is cell based, the proposed algorithm develops an access user based interference reconstruction procedure starting from the access user with maximum peak-value power. Simulation results indicate that compared to existing IC methods, the proposed algorithm expresses not only higher estimation precision but also lower computational complexity.

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“…In [15,16], a smart antenna based on a combined DoA and joint channel estimation scheme has been investigated for the European TD-CDMA standard applying joint data detection at the uplink receiver. A user-specific training sequence is used for a combined DoA and joint channel estimation.…”

Section: Introductionmentioning

confidence: 99%

An Adaptive Multiuser Detection Algorithm for CDMA Systems Using Antenna Diversity

Swamy

2010

Circuits Syst Signal Process

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Based on the minimum mean squared error (MMSE) between the data stream and the linear combiner output, a new multiuser detection (MUD) algorithm that combines space-time (ST) processing and antenna array on direct-sequence CDMA signals is proposed. The proposed ST-MUD algorithm is proved to be equivalent to two existing MMSE-based ST-MUD algorithms, and the theoretical BER performances for all the three algorithms are the same. The most attractive feature of the new ST-MUD algorithm is based on the fact that the new method does not require explicit estimation of channel and signaling information. This avoids any channel estimation error, and the method is thus more robust and more accurate than the other two ST-MUD algorithms in practical implementation. Adaptation of the proposed ST-MUD algorithm is implemented by using training sequences. Performance of this new multiuser detector is compared with that of two existing MMSE multiuser detectors and the conventional single-user space-time rake receiver through simulations. The proposed ST-MUD algorithm provides a performance better than existing algorithms and is especially suitable for practical CDMA systems.

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Smart antennas for combined DOA and joint channel estimation in time-slotted CDMA mobile radio systems with joint detection

Cited by 67 publications

References 18 publications

Cramer-Rao bounds for estimating range, velocity, and direction with an active array

Cramer-Rao bounds for estimating range, velocity, and direction with an active array

High Precision Multi-cell Channel Estimation Algorithm Based on Successive Interference Cancellation

An Adaptive Multiuser Detection Algorithm for CDMA Systems Using Antenna Diversity

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