Cooperative communication methods and devices

A space-time coded cooperative communication method for a wireless communication network, the network including a first communication device and a second communication device, each of the communication devices being associated with respective users and configured to communicate with a common destination, the first communication device being configured to transmit a first message to the second communication device and to the common destination in a first time slot, the second communication device being configured to transmit the first message as a first routed message, the method comprising the steps of:

• the common destination:
• receiving the first message from the first communication device in the first time slot and the first routed message from the second communication device in a second or third time slot;
• receiving a second message from the second communication device in the first or second time slot and a second routed message from the first communication device in the second or third time slot, the second routed message including the second message transmitted by the second communication device;
• converting the received first and second messages from time to frequency domain;
• and
• obtaining a first combination sequence by linearly combining the frequency domain first and second messages;
• obtaining a second combination sequence by linearly combining the first combination sequence and the first and second routed messages;
• dividing the first combination sequence or the second combination sequence by a channel related sequence which characterizes a first transmission path between the first communication device and the common destination, and a second transmission path between the second communication device and the destination;
• prior to decoding the received first and second messages, the common destination estimating a first channel parameter which characterizes the first transmission path based on a main training signal transmitted by the first communication device;
• and
• prior to transmitting the first message, the first communication device:
• transmitting an auxiliary training signal to the second communication device,
• obtaining an inter-device channel parameter which characterizes an inter-device transmission path between the first and the second communication device based on the training signal;
• and
• transmitting the inter-device channel parameter to the common destination;
• wherein the channel related sequence is obtained by combining the first channel parameter and a second channel parameter which characterizes the second transmission path.

A wireless communication network comprising a communication device configured for space-time coded cooperative communication with a second communication device, the communication device and the second communication device being associated with respective users and configured to communicate with a common destination in the wireless communication network, the communication device further configured to:

• transmit a first message to the second communication device for transmission to the common destination and to the common destination in a same time slot;
• receive a second message from the second communication device for transmission to the common destination;
• convert the received second message from time to frequency domain;
• obtain a first combination sequence by linearly combining the frequency domain first and second messages;
• and
• prior to transmitting the first message, transmitting an auxiliary training signal to the second communication device, and obtaining an inter-device channel parameter which characterizes an inter-device transmission path between the first and the second communication device based on the training signal;
• and
• transmitting the inter-device channel parameter to the common destination;
• the common destination further configured to:
• receive the first message directly from the first communication device;
• receive the second message directly from the second communication device;
• decode the received first and second messages and the first and second routed messages;
• convert the received first and second messages from time to frequency domain;
• obtain a first combination sequence by linearly combining the frequency domain first and second messages;
• obtain a second combination sequence by linearly combining the first combination sequence and the first and second routed messages;
• divide the first combination sequence or the second combination sequence by a channel related sequence which characterizes a first transmission path between the first communication device and the common destination, and a second transmission path between the second communication device and the common destination;
• prior to decoding the received first and second messages, estimating the first channel parameter based on a main training signal transmitted by the first communication device;
• wherein the channel related sequence is obtained by combining a first channel parameter which characterizes the first transmission path and a second channel parameter which characterizes the second transmission path.

A wireless communication network comprising a communication device which is configured for space-time coded cooperative communication with a second communication device in the wireless communication network, the communication device and the second communication device being associated with respective users and configured to communicate with a common destination of the wireless communication network, the communication device comprising an integrated circuit (IC) the IC further comprising:

• a processing unit configured to transmit a first message to the second communication device for transmission to the common destination and to the common destination in a same time slot;
• to receive a second message from the second communication device for transmission to the common destination;
• to convert the received second message from time to frequency domain;
• to obtain a first combination sequence by linearly combining the frequency domain first and second messages;
• prior to transmitting the first message, to transmit an auxiliary training signal to the second communication device;
• to obtain an inter-device channel parameter which characterizes an inter-device transmission path between the first and the second communication device based on the training signal;
• and to transmit the inter-device channel parameter to the common destination;
• the common destination configured to receive the first message directly from the first communication device;
• to receive the second message directly from the second communication device;
• to decode the received first and second messages and the first and second routed messages;
• to convert the received first and second messages from time to frequency domain;
• to obtain a first combination sequence by linearly combining the frequency domain first and second messages;
• to obtain a second combination sequence by linearly combining the first combination sequence and the first and second routed messages;
• to divide the first combination sequence or the second combination sequence by a channel related sequence which characterizes a first transmission path between the first communication device and the common destination, and a second transmission path between the second communication device and the destination;
• and to estimate a first channel parameter which characterizes the first transmission path based on a main training signal transmitted by the first communication device prior to decoding the received first and second messages;
• wherein the channel related sequence is obtained by combining the first channel parameter and a second channel parameter which characterizes the second transmission path.

An Integrated circuit (IC) for a base station of a wireless communication network including first and second communication devices configured for space-time coded cooperative communication, each communication device being associated with respective users and configured to communicate with the base station, the first communication device being configured to transmit a first message to the second communication device and to the base station in a first time slot, the second communication device being configured to transmit the first message as a first routed message, the IC including

• a processor configured to:
• receive the first message from the first communication device in the first time slot and the first routed message from the second communication device in a second or third time slot, and
• receive a second message from the second communication device in the first or second time slot and a second routed message from the first communication device in the second or third time slot, the second routed message including the second message transmitted by the second communication device;
• decode the received first and second messages and the first and second routed messages
• convert the received first and second messages from time to frequency domain;
• obtain a second combination sequence by linearly combining the first combination sequence and the first and second routed messages;
• divide the first combination sequence or the second combination sequence by a channel related sequence which characterizes a first transmission path between the first communication device and the base station, and a second transmission path between the second communication device and the base station;
• and
• estimate the first channel parameter based on a main training signal transmitted by the first communication device prior to decoding the received first and second messages;
• wherein the channel related sequence is obtained by combining the first channel parameter and a second channel parameter which characterizes the second transmission path.