TABLE OF CONTENTS A large number of physical layer cell identities (IDs) simplify the task of network planning. This is because neighboring cells are generally required to use different cell IDs. In the LTE system, a total of 504 unique physical layer cell identities are provided. A cell identity is derived from a physical layer cell identity group, 
in the range of 0 167 and another physical layer identity (within the cell-identity group) 
in the range 0 2 as shown in Table 9.1.
| PHY layer cell identity group | PHY layer identity | PHY layer cell identity |
|---|---|---|
| 0 | 0 | |
| 0 | 1 | 1 |
| 2 | 2 | |
| 0 | 3 | |
| 1 | 1 | 4 |
| 2 | 5 | |
| | | |
| 0 | 501 | |
| 167 | 1 | 502 |
| 2 | 503 |
The primary synchronization signal sequence denoted as d( n) is transmitted in the frequency-domain and is given as below:
| (9.10) |  |
where the ZC root sequence index u is 25, 29, 34 for = 0, 1, 2 respectively. The transmission of primary synchronization signal can use any of the four unicast antenna ports, that is, antenna port 0, 1, 2 or 3. It is also possible that a completely different antenna port from the antenna port 0, 1, 2 or 3 is used for PSS transmission. A cell can create a new antenna port by using one or more of the antenna ports among the available ports, that is, port 0, 1, 2 or...
