To respond to the traffic increases of recent years, 3GPP has been studying further enhancements for radio base stations. LTE-Advanced Release 13 specifies technologies to achieve two-dimensional radio base station antenna port mapping and increase the number of ports, radio performance requirements for AAS for more flexible area construction with combined antenna-transmission/reception functio...

We consider a user-centric co-operative cellular network, where base stations close to a mobile co-operate to detect its signal using a (joint) linear minimum-mean-square-error receiver. The base stations, which have multiple antennas, and mobiles are modeled as independent Poisson Point Processes to avoid dependence on specific node locations. Combining stochastic geometry and infinite random ...

We determine the feedback capacity region of a two user Gaussian multiple access channel (MAC) with multiple antennas at the base station and a single antenna at each user. The vector MAC and broadcast channels (BC) with a single antenna at the base station and multiple antennas at each user are shown to be equivalent to scalar MACs and BCs, respectively. We also determine the capacity enhancem...

1. Abstract: In mobile communications in urban area, it is a significant problem that blind spots of in the narrow street are caused by high buildings. In our previous works, a reflectarray antenna was developed to solve the problem [1]. However, the gain of reflectarray becomes very low when a very broad scattering angle is required. In this research, a new dual-antenna system is proposed, inc...

Abstnrer-Location finding for CDMA subscribers using an antenna army at the base station and deploying multiple base stations is studied in this paper. ' b o metbods are considered for radio location: measured time-of-arrival (TOA) and angle-of-anival (AOA), and algorithms to estimate them are presented. The estimated TOA and AOA fmm different base stations are combined via data fusion to estim...

A software antenna will be a key device realizing flexible and highly reliable wireless communications systems. The software antenna has been proposed to provide an effective means to cope with time-varying severe propagation environment by selecting an optimum algorithm continually. We call the scheme algorithm diversity. The technologies contain i) how to recognize the radio environment, ii) ...

This paper investigates the spatial and temporal correlation by measurements of an 8-element adaptive antenna array. The channel measurement data is gathered at a 2.154 GHz range outdoor radio channel. The measurement analysis is divided into three different categories: Investigation of spatial correlation between antenna elements at the base station (BS), spatial correlation of different mobil...

Frequency synchronization is a critical requirement for single-carrier frequency division multiple-access (SC-FDMA) uplink transmissions. Based on the key observation that the received signal at the base station can be formulated as the parallel factor analysis model, we present a joint carrier frequency offset (CFO) estimation and compensation scheme for SC-FDMA uplink transmissions with inter...

12  Abstract — We have proposed and demonstrated a novel architecture of a radio over fiber (RoF) system in this paper. In this downlink system, the base band data signals are carried by the optical millimeter-wave generated at the central station and converted to the electrical RF signal by a converter at the base station before we distribute them through antenna. Here we generate and transmi...