/**
*
* CPM (closest-pattern matching) is a wireless noise simulation model
- * based on statistical extraction from empirical noise data.
- * This model provides far more precise
- * software simulation environment by exploiting time-correlated noise
- * characteristic and shadowing effect as well as path-loss model. For
- * details, please refer to the paper
+ * based on statistical extraction from empirical noise data. This
+ * model provides far more precise software simulation environment by
+ * exploiting time-correlated noise characteristics. For details,
+ * please refer to the paper
*
* "Improving Wireless Simulation through Noise Modeling." HyungJune
* Lee and Philip Levis, IPSN 2007. You can find a copy at
sim_time_t end;
double power;
double reversePower;
+ int8_t strength;
bool lost;
bool ack;
message_t* msg;
else {
noise_val = (double)sim_noise_generate(node_id, quotient);
}
- dbg("CpmModelC", "OUT: noise_hash_generation()\n");
+ dbg("CpmModelC,Tal", "%s: OUT: noise_hash_generation(): %lf\n", sim_time_string(), noise_val);
return noise_val;
}
}
command bool Model.clearChannel() {
- dbg("CpmModelC", "Checking clear channel @ %s: %f <= %f \n", sim_time_string(), (double)noise_hash_generation(), clearThreshold);
- return noise_hash_generation() < clearThreshold;
+ dbg("CpmModelC", "Checking clear channel @ %s: %f <= %f \n", sim_time_string(), (double)packetNoise(NULL), clearThreshold);
+ return packetNoise(NULL) < clearThreshold;
}
void sim_gain_schedule_ack(int source, sim_time_t t, receive_message_t* r) {
mine->lost = 1;
}
if (!mine->lost) {
+ // Copy this receiver's packet signal strength to the metadata region
+ // of the packet. Note that this packet is actually shared across all
+ // receivers: a higher layer performs the copy.
+ tossim_metadata_t* meta = (tossim_metadata_t*)(&mine->msg->metadata);
+ meta->strength = mine->strength;
+
dbg_clear("CpmModelC,SNRLoss", " -signaling reception\n");
signal Model.receive(mine->msg);
if (mine->ack) {
rcv->end = endTime;
rcv->power = power;
rcv->reversePower = reversePower;
+ // The strength of a packet is the sum of the signal and noise. In most cases, this means
+ // the signal. By sampling this here, it assumes that the packet RSSI is sampled at
+ // the beginning of the packet. This is true for the CC2420, but is not true for all
+ // radios. But generalizing seems like complexity for minimal gain at this point.
+ rcv->strength = (int8_t)(floor(10.0 * log(pow(10.0, power/10.0) + pow(10.0, noiseStr/10.0)) / log(10.0)));
rcv->msg = msg;
rcv->lost = 0;
rcv->ack = receive;
-
// If I'm off, I never receive the packet, but I need to keep track of
// it in case I turn on and someone else starts sending me a weaker
// packet. So I don't set receiving to 1, but I keep track of
while (neighborEntry != NULL) {
int other = neighborEntry->mote;
- sim_gain_put(other, msg, endTime, ack && (other == dest), power + sim_gain_value(sim_node(), other), reversePower + sim_gain_value(other, sim_node()));
+ sim_gain_put(other, msg, endTime, ack, power + sim_gain_value(sim_node(), other), reversePower + sim_gain_value(other, sim_node()));
neighborEntry = sim_gain_next(neighborEntry);
}
}