UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C.  20549



                                  SCHEDULE 13G



                   Under the Securities Exchange Act of 1934
                              (Amendment No. 7 )*


                    INTERDIGITAL COMMUNICATIONS CORPORATION
--------------------------------------------------------------------------------
                                (Name of Issuer)


                                  COMMON STOCK
--------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                   45866A105
--------------------------------------------------------------------------------
                                 (CUSIP Number)


                                 July 31, 2001
--------------------------------------------------------------------------------
            (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

     [X]  Rule 13d-1(b)
     [_]  Rule 13d-1(c)
     [_]  Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).

                               Page 1 of 6 pages


  CUSIP No. 45866A105                13G                    Page 2 of 6 Pages
            ---------


------------------------------------------------------------------------------
      NAME OF REPORTING PERSONS
 1.   I.R.S. IDENTIFICATION NOs. OF ABOVE PERSONS

      HEARTLAND ADVISORS, INC.
      #39-1078128
------------------------------------------------------------------------------
      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 2.                                                             (a) [_]
                                                                (b) [_]

------------------------------------------------------------------------------
      SEC USE ONLY
 3.


------------------------------------------------------------------------------
      CITIZENSHIP OR PLACE OF ORGANIZATION
 4.

      WISCONSIN, U.S.A.
------------------------------------------------------------------------------
                          SOLE VOTING POWER
                     5.
     NUMBER OF
                          645,250
      SHARES       -----------------------------------------------------------
                          SHARED VOTING POWER
   BENEFICIALLY      6.

     OWNED BY             None
                   -----------------------------------------------------------
       EACH               SOLE DISPOSITIVE POWER
                     7.
    REPORTING
                          2,487,050
      PERSON       -----------------------------------------------------------
                          SHARED DISPOSITIVE POWER
       WITH          8.
                          None
------------------------------------------------------------------------------
      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 9.
      2,487,050
------------------------------------------------------------------------------
      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
10.
                                                                    [_]
 ------------------------------------------------------------------------------
      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11.

      4.5%
------------------------------------------------------------------------------
      TYPE OF REPORTING PERSON
12.
      IA
------------------------------------------------------------------------------



  CUSIP No. 45866A105                13G                    Page 3 of 6 Pages
            ---------


------------------------------------------------------------------------------
      NAME OF REPORTING PERSONS
 1.   I.R.S. IDENTIFICATION NOs. OF ABOVE PERSONS

      WILLIAM J. NASGOVITZ
      395-42-0703
------------------------------------------------------------------------------
      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
 2.                                                             (a) [_]
                                                                (b) [_]

------------------------------------------------------------------------------
      SEC USE ONLY
 3.


------------------------------------------------------------------------------
      CITIZENSHIP OR PLACE OF ORGANIZATION
 4.

      U.S.A.
------------------------------------------------------------------------------
                          SOLE VOTING POWER
                     5.
     NUMBER OF
                          1,700,000
      SHARES       -----------------------------------------------------------
                          SHARED VOTING POWER
   BENEFICIALLY      6.

     OWNED BY             None
                   -----------------------------------------------------------
       EACH               SOLE DISPOSITIVE POWER
                     7.
    REPORTING
                          None
      PERSON       -----------------------------------------------------------
                          SHARED DISPOSITIVE POWER
       WITH          8.
                          None
------------------------------------------------------------------------------
      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 9.
      1,700,000
------------------------------------------------------------------------------
      CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
10.
                                                                    [_]
 ------------------------------------------------------------------------------
      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11.

      3.1%
------------------------------------------------------------------------------
      TYPE OF REPORTING PERSON
12.
      IN
------------------------------------------------------------------------------




CUSIP NUMBER  45866A105                   Page 4 Of 6 Pages

Item 1.
    (a) Name of Issuer:    InterDigital Communications Corporation
        --------------


    (b) Address of Issuer's Principal Executive Offices:
        -----------------------------------------------
        781 Third Avenue
        King of Prussia, PA  19406-1409

Item 2.
    (a) Name of Person Filing:   (1) Heartland Advisors, Inc.
        ---------------------
                                 (2) William J. Nasgovitz


    (b) Address of Principal Business Office:
        ------------------------------------
         (1) 789 North Water Street                (2)  789 North Water Street
             Milwaukee, WI  53202                       Milwaukee, WI  53202

    (c) Citizenship:  Heartland Advisors is a Wisconsin corporation.
        -----------
                      William J. Nasgovitz - U.S.A

    (d) Title of Class of Securities:  Common Stock
        ----------------------------

    (e) CUSIP Number:  45866A105
        ------------

Item 3. The persons filing this Schedule 13G are Heartland Advisors, Inc., an
investment adviser registered with the SEC, and William J. Nasgovitz, President
and principal shareholder of Heartland Advisors, Inc. Mr. Nasgovitz joins in
this filing pursuant to SEC staff positions authorizing certain individuals in
similar situations to join in a filing with a controlled entity eligible to file
on Schedule 13G. The reporting persons do not admit that they constitute a
group.

Item 4. Ownership.
        ---------

    For information on ownership, voting and dispositive power with respect to
the above listed shares, see Items 5-9 of the Cover Page.


Item 5. Ownership of Five Percent or Less of a Class.
        --------------------------------------------

      If this statement is being filed to report the fact that as of the date
hereof the reporting person has ceased to be the beneficial owner of more than
five percent of the class of securities, check the following:[ X]

Item 6. Ownership of more than Five Percent on Behalf of Another
        --------------------------------------------------------
        Person.
        ------

      Not Applicable.


Item 7. Identification and Classification of the Subsidiary Which Acquired the
        ----------------------------------------------------------------------
Security Being Reported on By the Parent Holding Company.
--------------------------------------------------------


          Not Applicable.


Item 8. Identification and Classification of Members of the Group.
        ---------------------------------------------------------


          Not Applicable.


Item 9. Notice of Dissolution of Group.
        ------------------------------


          Not Applicable.


Item 10.  Certification.
          -------------

      By signing below, the undersigned certify that, to the best of their
knowledge and belief, the securities referred to above were acquired and are
held in the ordinary course of business and were not acquired and are not held
for the purpose of or with the effect of changing or influencing the control of
the issuer of the securities and were not acquired and are not held in
connection with or as a participant in any transaction having that purpose or
effect.

                                   SIGNATURE


      After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.



DATE:  August 3, 2001



WILLIAM J. NASGOVITZ                           HEARTLAND ADVISORS, INC.

By: /s/  PAUL T. BESTE                         By: /s/ PAUL T. BESTE
   -------------------                            -------------------
   Paul T. Beste                                       Paul T. Beste
   As Attorney in Fact for                             Chief Operating Officer
   William J. Nasgovitz



EXHIBIT INDEX

     Exhibit 1      Joint Filing Agreement


EXHIBIT 1



                             Joint Filing Agreement


The undersigned persons agree and consent to the joint filing on their behalf of
this Schedule 13G in connection with their beneficial ownership of InterDigital
Communications Corporation at July 31, 2001.



WILLIAM J. NASGOVITZ

By: /s/ PAUL T. BESTE
    -----------------
        Paul T. Beste
As Attorney in Fact for William J. Nasgovitz



HEARTLAND ADVISORS, INC.


By: /s/ PAUL T. BESTE
    -----------------
        Paul T. Beste
        Chief Operating Officer