# A Multiple Access Protocol Based on Gray Forecast for Satellite Network
## 6 Simulation Analysis
When the channel load is small, the queue stacking number of the three protocols almost has no difference because the data packets in the user queue do not need to be queued when the system channel load is small. When the channel load increases, the number of queues in the CFDAMA-GF protocol is significantly lower than those of the CFDAMA and PURE-DAMA methods because the CFDAMA-GF protocol adds a gray forecast method to probe the source when a user gains access, thereby creating a user's current appointment. The number of timeslots is greater than the number of queued packets in the current queue, ensuring that packets arriving at the next moment can be sent in time without queuing. Figure 5 shows a user's average communication delay versus channel load. When the channel load is small, the average delay performance of PURE-DAMA is poorer than those of CFDAMA-PB and CFDAMA-GF because the pure DAMA protocol assigns the demand during the satellite resource allocation process and does not do any processing for the remaining timeslots, thereby saving a part of the timeslot's resources. The average end-to-end delay performances of CFDAMA-PB and CFDAMA-GF are similar because the data packet intensity sent out by the data source is not high when the channel load is low, and only a few users have data transmission demand. Thus, the satellite  
Figure 4: Comparison of the number of queued packets and channel load. Figure 5: Comparison of average delay and channel load. allocates these users during the demand assignment process, and all users' data packets can be transmitted and forwarded within one frame. When the channel load increases, the burst strength of data packets generated by the source increases, and the number of users with service transmission increases, resulting in an insufficient number of remaining timeslots in the satellite after the demand assignment is allocated. The average delay between the CFDAMA-PB and pure DAMA protocol slightly varies. Moreover, the CFDAMA-PB protocol may cause the users with a large demand to fail in obtaining timeslot allocation in time. The CFDAMA-GF protocol sorts users according to the timeslots' reservation size from high to low when satellites are allocated by demand assignment. In the next step, the corresponding priority number is set. A high number of users with high reservations corresponds to a high priority. This relationship ensures that the user of the slot reservation request can be allocated in time when the channel load increases. A user with a substantial demand preferentially performs processing. Thus, the average communication delay performance of CFDAMA-GF is better than that of the two other methods. Figure 6 shows the relationship between the average of communication delay and the number of users. When the number of users increases, the average delay increases. When the number of users with access is small, no gaps exist in the delay performance of the three protocols. The CFDAMA-GF delay does not have a clear advantage because the protocol has a gray forecast process and sorts calculations when a user gains access, resulting in a slightly large average delay. When the number of users in the system continuously increases, the average delay of the CFDAMA-GF protocol is better than that of scheduling appointments and priorities. When the number of users further increases, the current service requirements can be sent in time to enable each user to access them in time. Users with a high demand can preferentially obtain timeslot allocations, thereby reducing the average end-to-end delay. Figure 7 shows the relationship between the average number of stacking packets in the queue and the number of users. When the number of users with access increases, the number of queues increases. The number of service packets and the average number of queues increase as the number of users increases. Figure 7 further illustrates that the performance of the three protocols is similar when the number of users and the number of service packets are small.