C.2 Multi-path case

25.1733GPPRelease 17Requirements for support of Assisted Galileo and Additional Navigation Satellite Systems (A-GANSS) Time Division Duplex (TDD)TS

Doppler frequency difference between direct and reflected signal paths is applied to the carrier and code frequencies. The Carrier and Code Doppler frequencies of LOS and multi-path for GANSS signals are defined in table C.2-1.

Table C.2-1: Multipath case

Initial Relative Delay
[m]

Carrier Doppler frequency of tap [Hz]

Code Doppler frequency of tap [Hz]

Relative mean Power [dB]

0

Fd

Fd / N

0

X

Fd-0.1

(Fd-0.1) /N

Y

Note: Discrete Doppler frequency is used for each tap.

Where the X and Y depends on the GNSS signal type and is shown in table C.2-2, and N is the ratio between the transmitted carrier frequency of the signals and the transmitted chip rate as shown in table C.2-3 (where k in table C.2-3 is the GLONASS frequency channel number).

Table C.2-2: Relative Delay and Attenuation of Non Line of Sight Signals

System

Signals

X [m]

Y [dB]

Galileo

E1

125

-4.5

E5a

15

-6

E5b

15

-6

GPS/Modernized GPS

L1 C/A

150

-6

L1C

125

-4.5

L2C

150

-6

L5

15

-6

GLONASS

G1

275

-12.5

G2

275

-12.5

BDS

B1I

75

-4.5

Table C.2-3: Ratio between the transmitted carrier frequency of the signals and the transmitted chip rate

System

Signals

N

Galileo

E1

1540

E5a

115

E5b

118

GPS/Modernized GPS

L1 C/A

1540

L1C

1540

L2C

1200

L5

115

GLONASS

G1

3135.03 + k  1.10

G2

2438.36 + k  0.86

BDS

B1I

763

The initial carrier phase difference between taps shall be randomly selected between 0 and 2. The initial value shall have uniform random distribution.

Annex D (normative): Measurement sequence chart