A method and apparatus for allocating subcarriers in an orthogonal frequency division multiple access (OFDMA) system is described. In one embodiment, the method comprises allocating at least one diversity cluster of subcarriers to a first subscriber and allocating at least one coherence cluster to a second subscriber.

Ofdma with adaptive subcarrier-cluster configuration and selective loading

Covariance Matching Estimation Techniques for Array Signal Processing Applications

Estimation of nominal direction of arrival and angular spread using an array of sensors

The disclosure describes a novel Time Difference of Arrival (TDOA) method (500) and system (100, 600 and 700) for determining the position of a first mobile radio terminal (108) within an associated mobile radio system (100, 600 and 700), which is based on Time of Arrival (TOA) measurements, including a plurality of radio base stations (BS1, BS2, BS3), measuring devices (130), network controller (110), and service node (103). The measuring devices are synchronized in otherwise unsynchronized radio base stations (BS1, BS2, BS3). The measuring devices (130) measure TOA on demand and (optionally) Direction of Arrival (DOA), on a digital uplink time slot (301 and 302) or on digital information on an analog uplink traffic channel in one or more radio base stations (BS1, BS2 and BS3). The TOA and DOA information and the traffic channel number are reported to a Mobile Services Switching Center (102), which obtains the first mobile terminal's (108) identity from the traffic channel number and sends the terminal identity and TOA and DOA measurement information to a Service Node (103). The Service Node (103) calculates the position of the first mobile radio terminal (108) using the TOA information (supplemented by the DOA information when available). A second mobile radio terminal (601) is colocated on a mobile platform (auto, emergency vehicle, etc.) with one of the radio base stations (BS1, BS2 or BS3), which can be moved into relatively close proximity with the first mobile radio terminal (103). Consequently, by moving one of the radio base stations (BS1, BS2 or BS3) close to the region of interest (near the first mobile radio terminal (108)), the position determination accuracy is significantly improved.

Method and system for determining the position of mobile radio terminals

Multi-carrier communications with adaptive cluster configuration and switching

This paper summarizes some of the antenna array work at Ericsson. The use of antenna arrays in a random frequency hopping GSM system is treated and receiver/transmitter structures are described. Results from simulations and propagation measurements are presented and compared with theoretical results. >

U. Forssn

Papers

Adaptive antenna arrays for GSM900/DCS1800