I found this paper very useful.

ABSTRACT

Wireless sensor networks promise fine-grain monitoring  in a wide variety of environments. Many of these  environments (e.g., indoor environments or habitats) can be harsh for wireless communication. From a networking perspective, the most basic aspect of wireless communication is the packet delivery performance: the spatio-temporal characteristics of packet loss, and its  environmental dependence.

These factors will deeply impact the performance of data acquisition from these networks.

In this paper, we report on a systematic medium-scale (up to sixty nodes) measurement of packet delivery in three different environments: an indoor office building, a habitat with moderate foliage, and an open parking lot. Our  findings have interesting implications for the design and  evaluation of routing and medium-access protocols for  sensor networks.

via Understanding Packet Delivery Performance In Dense Wireless Sensor Networks