Full-rate distributed space-time codes for cooperative communications

A method, comprising:

• for a relay node of a set of relay nodes,
• receiving, by a system including a processor, a signal from a source node;
• determining a new data vector based, at least, on a signal vector and a signature vector of the relay node, wherein the signature vector is determined based on a function of a total number of relay nodes in the set of relay nodes and the signal vector is modified based on a power scaling factor determined based on a condition that respective average transmit powers of the relay nodes are approximately equal or equal to a same value;
• and
• transmitting the new data vector substantially concurrently or concurrently with other ones of the set of relay nodes.

A node, comprising:

• a codeword creation component configured to generate a codeword to transmit that corresponds to a block of data at the node;
• a power management component configured to determine a power allocation at which to transmit a first part of the codeword, wherein the power allocation is a function of a number of relay nodes in a network, and the node is a source node distinct from the relay nodes;
• and
• a signal transmitting component configured to:
• transmit the first part of the codeword to a destination node and at least one of the relay nodes in a first time period;
• and
• transmit a second part of the codeword to the destination node during a second time.

A node, comprising:

• a signal receiving component configured to receive a first signal from a source node, the first signal being associated with a signal vector;
• a component-wise multiplication component configured to determine a new data vector based, at least, on the signal vector and a signature vector of the node by performing component-wise multiplication of the signal vector and the signature vector of the node, wherein the signature vector is a function of a number of the plurality of nodes and the signal vector is weighted by a power scaling factor determined to yield an approximately equal or equal average transmit power for the plurality of nodes;
• and
• a signal transmitting component configured to transmit the new data vector.

A node, comprising:

• a signal receiving component configured to substantially concurrently or concurrently receive a signal from a source node and a signal from a relay node, wherein the relay node is one of a plurality of relay nodes in a network comprising the relay nodes,
• wherein the signal from the relay node comprises an amplified signal, the amplified signal being a function of a first part of a codeword created at the source node, and a signature vector associated with the relay node,
• wherein the signature vector is a function of a number of the relay nodes,
• wherein the amplified signal is amplified based on a power scaling factor determined to result in average transmit powers of the relay nodes being approximately equal or equal to a same value, and
• wherein the signal from the source node comprises a second part of the codeword created at the source node;
• and
• a maximum likelihood decoding component configured to decode the signal from the source node and the signal from the relay node based on maximum likelihood decoding.

An apparatus comprising:

• means for receiving a signal from a source node;
• means for determining a new data vector based, at least, on a signal vector and a signature vector of the apparatus, wherein the apparatus is one of a plurality of apparatuses in a network comprising the apparatuses, and wherein the signature vector is based on a function of a total number of the plurality of apparatuses, wherein the signal vector is modified as a function of a power scaling factor, and wherein the power scaling factor is determined to set average transmit powers of the plurality of apparatuses approximately equal or equal to a same value;
• and
• means for transmitting the new data vector substantially concurrently or concurrently with other ones of the plurality of apparatuses.

A tangible computer-readable medium having instructions stored thereon, the instructions comprising:

• instructions to receive a signal from a source node;
• instructions to determine a new data vector based, at least, on a signal vector and a signature vector of the apparatus, wherein the apparatus is one of a plurality of apparatuses in a network comprising the apparatuses, wherein the signature vector is determined based on a function of a total number of the plurality of apparatuses, and wherein the signal vector is modified based on a power scaling factor determined to result in average transmit powers of the plurality of apparatuses being approximately equal or equal to a same value;
• and
• instructions to transmit the new data vector substantially concurrently or concurrently with other ones of the plurality of apparatuses.