Telefonaktiebolaget Lm Ericsson (publ)

Sara Mazur

Bo Hagerman

Christofer Lindheimer

Jonas B Karlsson

Fredrik Bengt Ovesj&ouml;

Johan Moln&ouml;

Patrik Nils Lundqvist

Jan Lindskog

Fredric Carl Kronestedt

Walter Ghisler

Bjorn Johannisson

Ulf Goran Forssen

Bjorn O Gudmundson

Thomas Ostman

Marlene Yared

S&ouml;ren Andersson

Ulf Forss&eacute;n

Gunnar Thrysin

The present invention relates to radio systems and, more particularly, to a method and apparatus for receiving radio signals with the aid of beams generated by antenna assemblies. For each of the beams in a first of the antenna assemblies there is a beam in the second of the antenna assemblies that covers the same space area. Signals received by the second are delayed relative to signals received by the first of the antenna assemblies. Then signals from the first antenna assembly are combined with signals from the second of the antenna assemblies. The combined signals derive from beams covering the same space area. Each combined signal is then radio received in a joint radio receiver. A DOA-estimation can be calculated on the basis of radio received signals derived from all beams.

Methods and apparatus in antenna diversity systems for estimation of direction of arrival

A method and device for making measurements on a control channel carrier that is not transmitting continuously with constant power is disclosed. In a system transmitting control on, e.g., one timeslot and not keeping a constant power on the other timeslots, the invention makes sure that, e.g., a mobile station always opens its measurement window during the control channel timeslot. A measurement window is made significantly shorter than a timeslot duration.

Methods and apparatus for measuring control carrier signal strength in wireless communications systems employing discontinuous control carrier transmissions

A method and system are disclosed for making inter-cell handoffs to a cell of a base station including a directional antenna array. The handoff algorithm includes taking into account uplink direction of arrival measurements in at least one candidate target base station, made on signals from the mobile radio terminal to it's serving base station, and directly after handoff using a directional narrow lobe from the antenna array. The narrow lobe can be used immediately after the handoff in the radio base stations that have antenna arrays, by including the direction (of arrival information) to the mobile radio terminal in the handoff order to the target base station. Also disclosed are a method and system for measuring uplink interference on idle narrow lobe traffic channels, and using this information when selecting at handoff a target base station and traffic channel.

Method and system for improving handoffs in cellular mobile radio systems

Multiple code sets are introduced in the downlink of a CDMA system to allow for more connections in each cell. The codes are then allocated to different users taking into account the interference therebetween. The interference depends on the antenna gains, transmission powers used and cross-correlations between codes. By estimating these parameters the interference can be minimized in the code allocation process. Since the allocation of codes and code sets to geographical areas within a cell may change over time, code handoff is supported.

Code allocation for radiocommunication systems

A method of obtaining cell specific information for a dual-mode mobile station (MS) operating in an overlaid network operating on different frequency bandwidths and time slot structures such as a combined D-AMPS and EDGE described in the ETSI Enhanced Data Rates for GSM Evolution (EDGE) specification. The combined networks operating on 30 kHz and 200 kHz respectively having a combined circuit switched and packet switched capability. An MS camping in packet mode is able to perform cell selection/reselection on a particular network by scanning and reading the appropriate control channels of the associated network. For example, in a first aspect of the invention, the MS periodically scans both the control channels on the 30 kHz network to read related cell information and the control channels of the 200 kHz network to read related cell information associated therewith. In a second aspect of the invention, the MS scans the 30 kHz control channels to read the cell information and, if cell reselection occurs, then scans the 200 kHz control channels. In a third aspect, the MS scans and reads the 200 kHz control channels for cell information and, in response to a page from the 30 kHz network, scans control channels associated with the 30 kHz network. A fourth aspect includes the situation where both 30 kHz and 200 kHz cells are coordinated. The MS can then scan and read the control channels from either network and obtain a pointer to the control channels of the other network.

Retrieving cell information in an overlaid circuit switched and packet switched wireless telecommunication network

The present invention describes a method of migrating a mobile station, operating within an integrated D-AMPS/EDGE wireless telecommunication network, from the D-AMPS packet portion of the network to the EDGE/GPRS packet portion of the network. The technique includes accessing the control channels of both the D-AMPS and EDGE networks in order to obtain the necessary timing advance and packet transfer identifier for use with the GPRS packet system. In an embodiment of the invention, the MS makes a first access on a D-AMPS control channel to obtain a pointer to a reserved radio block on an EDGE packet control channel. The MS makes a second access on the EDGE control channel as specified by the reserved radio block which contains a particular frequency and timeslot location. The MS then sends a series of shortened bursts to the network such that a Timing Advance Index (TAI) value is calculated from the bursts and sent back to the MS. A packet data channel (PDCH) is assigned by the network and sent to the MS to perform the packet data transfer using the estimated TAI and assigned TFI.

Mobile station migration from D-AMPS packet system to edge/GPRS packet system in an integrated wireless network

A system and method for a synchronized packet data communication system is described. Briefly control channels are transmitted in a reuse pattern defined by both frequency and timeslot division. Each timeslot division is such that different timeslot groups included in the repetition pattern are separated by at least one timeslot. No traffic data transmissions occur simultaneous to the control channel transmissions. Furthermore, a synchronization channel is introduced to be transmitted on the same physical channel as other packet common control channels.

High speed data communication system and method

In a cellular telecommunications network, a method and apparatus is disclosed for providing a substantial gain in downlink C/I by means of antenna pattern downtilt while still maintaining the coverage limiting signal strength in the uplink by the use of different antenna pattern downtilt for the transmit and receive antenna patterns.

Uplink and downlink transmission quality improvement by differentiated base station antenna pattern downtilt

Mobile stations using antenna diversity are described. Techniques for combining CDMA signals received over plural antennas at a mobile unit are provided which suppress interference from undesired base stations.

Mobile station having plural antenna elements and interference

Power control apparatus and an associated method for a transmitting station operable in a TDMA communication system. The transmitting station includes transmitter branches for communicating communication signal bursts during selected time slots. Communication signal bursts transmitted upon adjacent time slots partially overlap so that a receiving station is able to extract information from a communication signal burst transmitted upon an adjacent time slot.

Power control apparatus, and an associated method, for TDMA transmitter

The disclosure describes a novel Time Difference of Arrival (TDOA) method and system for determining the position of a mobile radio terminal within an associated mobile radio system, which is based on Time of Arrival (TOA) measurements, including a plurality of radio base stations, measuring devices, network controller, and service node. The measuring devices are synchronized in otherwise unsynchronized radio base stations. The measuring devices measure TOA on demand and (optionally) Direction of Arrival (DOA), on a digital uplink time slot or on digital information on an analog uplink traffic channel in one or more radio base stations. The TOA and DOA information and the traffic channel number are reported to a Mobile Services Switching Center, which obtains the mobile terminal's identity from the traffic channel number and sends the terminal identity and TOA and DOA measurement information to a Service Node. The Service Node calculates the position of the mobile radio terminal using the TOA information (supplemented by the DOA information when available).

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Bromma, Sweden

Sara Mazur