In this paper, a novel and simple PN code
with a 10 bit sequence length is developed.
The Code division multiple access (CDMA) enhanced security based on the advanced encryption standard (AES) operation and it used 128, 192, and 256 bits AES-CDMA PN code
sizes to raise the security level against eavesdropping .
These new patents include US Patent 9,164,722, titled, 'Method for Ensuring Media Stream Security in IP Multimedia Sub-System'; European patent 2,061,170, titled, "OFDM Transmitter and Receiver', which was granted in Germany, France and Great Britain; European patent 1,835,617, titled, 'PN Code
Generation Apparatus and Method Thereof', which was granted in Germany, France and Great Britain, and patent 45432 titled, 'Method for Implementing Access', which was granted in Thailand..
Code-division multiple access (CDMA), created by Qualcomm, works by assigning a different pseudorandom or pseudonoise code (PN code
) specific to each phone.
As shown in the previous section, a PN code
with different cyclic shifts may be used to encode each data symbol.
A PN code
with length N will cause the bandwidth efficiency dropping to 1/N times of the original OFDM system.
Starzyk, "Hardware Implementation for Fast Convolution with a PN Code
Using Field Programmable Gate Array," Proceedings of the 33rd Southeastern Symposium on System Theory, Athens, OH, March 2001, pp.
 develop a long PN code
based direct sequence spread spectrum (DSSS) flow marking technique for invisibly tracing suspect anonymous flows.
In order to be able to detect a PN modulated measurement signal, it is necessary to lock on the PN code
The PN code
acquisition is instantaneous and burst data rate is configurable.
The system uses direct sequence spread spectrum with 128 chips per bit (PN code
of 128 = 128 chips per bit), and therefore, has process gains of about 21 dB.