Telefonaktiebolaget Lm Ericsson (publ)

Jichang Liao

Xiaoliang Du

Youping Su

Vimar Björk

Ning Sun

Jiangyan Peng

Erik Hammarberg

A method for calibrating an active antenna system (AAS). The AAS comprises a radio unit and an antenna array. The radio unit comprises a plurality of transceiver branches. The method comprises calibrating at least one, but less then all, out of the plurality of transceiver branches as reference branch or branches. The method further comprises calibrating non-calibrated transceiver branch or branches out of the plurality of transceiver branches while the antenna array and the radio unit are connected. The disclosure further relates to a method for onsite automatic maintenance of an active antenna system, and to an active antenna system.

Method and active antenna system in telecommunication networks

A method performed by a radio network node for deciding an Automatic Gain Control (AGC) mode to be used for a received signal in a wireless communications network is provided. The radio network node estimates () a type of interference scenario affecting the received signal and obtains () information about channel quality of channels between the radio network node and connected wireless devices. Based on the estimated type of interference scenario and the obtained information about the channel quality, the radio network node dynamically decides () for the received signal, which AGC mode out of the following ACG modes to be used: &#x2014;a slow AGC using a release timer for releasing an AGC state, &#x2014;a fast AGC using a release timer for releasing an AGC state, and&#x2014;a fast AGC using a trigger timer triggering an AGC state a first time interval before an interference period, and the release timer releasing the AGC state a second time interval after said interference period ends.

Radio network node and method therein for deciding AGC mode for a received signal in a wireless communications network

The embodiments disclose a method and apparatus for automatic gain control. The apparatus comprises a first gain controlled element, a second gain controlled element, a first gain control device, a second gain control device and a first simulator. The first gain controlled element and the second gain controlled element each has a signal input, a gain control input and a signal output. The first gain controlled element and the second gain controlled element are coupled in series and one or more power elements coupled between the first gain controlled element and the second gain controlled element. The signal input of the first gain controlled element constitutes an input of the automatic gain control apparatus. The first gain control device has a pre-detection input which is coupled to the signal input of the first gain controlled element and an output which drives the gain control input of the first gain controlled element. The second gain control device has a pre-detection input and an output which drives the gain control input of the second gain controlled element. The first simulator is coupled between the signal input of the first gain controlled element and the pre-detection input of the second gain control device, which is used to simulate frequency response of the one or more power elements between the first gain controlled element and the second gain controlled element, such that a signal received by the pre-detection input of the second gain control device is matched with a signal received by the signal input of the second gain controlled element.

Method and apparatus for automatic gain control

A tower mounted amplifier and a filter. The filter includes a transmission part having a first tunable portion and a reception part having a second tunable portion and a third tunable portion. The transmission part is coupled between a first port and a second port. The second tunable portion of the reception part is coupled between the first port and a third port, and the third tunable portion of the reception part is coupled between a fourth port and the second port. The first tunable portion is configured to work in a first frequency range different from a first pass band in which the second and third tunable portions are controlled to work when a radio frequency signal is to be transmitted from the first port to the second port, the radio frequency signal being rejected by the first tunable portion to the second port.

Tower mounted amplifier and filter thereof

A high performance switch module to filter a radio frequency signal and to selectively connect to an output includes a filter unit and a plurality of switches. The filter unit has a filter configured to connect to the radio frequency signal and having a plurality of parallel output ports. The plurality of switches is connected between the plurality of parallel output ports and the output, the plurality of switches configured to connect to a control input to selectively connect an output port of the plurality of parallel output ports to the output and to selectively connect a remainder of the plurality of parallel output ports to a connection providing a substantially full reflection to the remainder of the plurality of parallel output ports of the filter unit.

Low noise amplifier module and method of implementation

The invention discloses a wideband receiver and a base station in a communication network. The wideband receiver comprises an Intermediate Frequency (IF) frequency control module, a frequency synthesizer, a mixer and an analog-to-digital converter (ADC). The IF frequency control module comprises an interference detector adapted to detect interference condition on at least one frequency band, and an IF frequency selector adapted to select an IF frequency based on the detected interference condition from the interference detector. The IF frequency is selected to avoid high interference mixed product of the mixer occurring in used channel. The frequency synthesizer generates an oscillator signal of the selected IF frequency, the mixer down converts a RF signal to an IF signal using the oscillator signal of the selected IF frequency, and the ADC converts the IF signal to baseband data.

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Beijing, China

Jichang Liao