TEMS INVESTIGATION SCANNERS FAQS

1(a). What is the reference point for the signal level measurement for all SeeGull scanner? Is the signal level already added in the antenna connector on the scanner or has it been included in been included in the the antenna gain and cable loss?

(b). What are the parameters of provided magnetic mount antenna?

2. PCTEL LX Tri-band and MM2 scanners are now shipped with the second GPS receiver removed.

3. How do I scan for IS95/CDMA2000 pilots that are far away? I.e when the signal's travel time exceeds 64 chips in time.

4. Why is PN Increment disabled when selecting EVDO with a PCTEL scanner?

Answers

1(a). What is the reference point for the signal level measurement for all SeeGull scanner?

Is the signal level already added in the antenna connector on the scanner or has it been included in been included in the the antenna gain and cable loss?

The reference point is in the scanner. The signal level provided by the scanner is the level measured at the connector of the scanner. No changes are made inside the scanner to compensate for antenna or cable loss.

(b). What are the parameters of provided magnetic mount antenna?

The antenna itself is a 0dBd gain antenna.

The SMARTEQ cable loss is specified at 1.86dB/meter cable at 2GHz maximum. If the length of the cable is 2.6m, that would give a maximum loss of 4.65 dB at 2GHz from the antenna to the scanner.

Following table shows the attenuation in diferent frequencies.

2. PCTEL LX Tri-band and MM2 scanners are now shipped with the second GPS receiver removed.

The following below is only an example for an LX Triband GSM/WCDMA Scanner:
This means that in S/N 01710133 and higher, it is only the WCDMA scanner part that contains a GPS.

The scanner may also be checked by the Part Number information on the scanner label, the new scanner says "*06030A*" (previously only "*06030*").
For a TEMS Investigation user this means that:

1. The LX GSM scanner port must be connected as "SeeGull LX GSM" (manually added prior to TEMS Investigation 8.1, auto-sensed correctly from TEMS Investigation 8.1)
2. If only GSM scan is performed the data will not be GPS positioned unless:
   a) an external GPS is connected
   b) the LX WCDMA scanner port is connected as "SeeGull LX WCDMA with GPS" and one WCDMA scan is first started (it might be stopped since GPS position messages continues anyway)
   2 b) will not work if the user has a GSM only license, i.e. then 2 a) must be used.

3. How do I scan for IS95/CDMA2000 pilots that are far away? I.e when the signal's travel time exceeds 64 chips in time.

You can use PN Increment

The user selects "PN Increment (1-15)" , "Start Pilot (0 or 1)" and "Max Cell Radius (1.6 - 124.9 km, default = 15,6 km)"

Example values can be 4, 0, 15.6

What happends is that available user selectable pilots will be 0, 4, 8, 12 etc. for pilot scan.

Lets say that the user checks 4 then 5, 6 and 7 will be selected in the background and fed into the scan order.

Before the order is sent to the scanner it is validated toward the cell radius.
If the cell radius is too large compared to the pilot increment the user is warned.
In the window given by PN increment, the decoder tries to find the strongest peak. If PN increment=4 the decoder searches for the strongest peak among 0, 1, 2 and 3. If for instance 2 is the strongest then we will assume that it's a delayed signal that really belongs to PN 0 and delay is set delay=delay + 64 * 2

4. Why is PN Increment disabled when selecting EVDO with a PCTEL scanner?

The same method of aggregating CDMA pilot energy cannot be used in EVDO.
The fundamental reason is that CDMA’s pilot is in a continuous format with each pilot/segment length of 64 chips.
However, each EVDO’s pilot contains 96 chips with 32 chips overlapped between pilots (PN1’s last 32 chips is PN2’s first 32 chips).
EVDO’s way of arranging pilots results in the correlation peaks/energy is not linearly "delayed" to the next pilot when signal travels a long distance.(the text above comes from PCTEL)
Instead you have to use chip window size "wide" or "wider". It increases the widow to 128 for wide and to 256 for wider.