Techniques for data gathering in large-scale wireless sensor networks are described. A data collection device receives aggregate data from at least one sensor node of a group of N sensor nodes. The aggregate data includes M weighted sums. Each of the M weighted sums includes a respective sum of N products each of which being a product of a respective coefficient and a sensor reading from a respective one of the N sensor nodes. M and N are positive integers and M is less than N. Computation is performed on the aggregate data to recover sensor readings from the N sensor nodes.